Horticultural Hints – September


September 2017

What a difference a year makes.  A year ago, much of New England and all of Massachusetts was in drought condition, with much of eastern Massachusetts classified as ‘Extreme’.  Then came fall rains and a wet winter and spring.  Here in the Greater Boston area, we are about five inches ahead of ‘normal’ precipitation through July, but August was a dry month.  Unless we get significant rainfall (an inch a week) you will need to water, particularly anything planted in 2017.

In the Vegetable Garden.  It’s planting time again.  If you put lettuce, arugula, spinach and even pea seeds in the bare areas of your garden at the beginning of September, you can have a fresh crop before the weather turns too cold.  And you can stretch the season even further by using floating row covers—lightweight cloth—over the plants on cool nights.

‘Top’ your tomatoes at the beginning of September and they will put their energy into ripening green tomatoes rather than forming new ones.

Tomatoes have taken over center stage now, and perhaps your kitchen counter.  But they cannot tolerate cool temperatures so remove the topmost growth on plants to encourage ripening what is already on the vine, instead of producing more fruit that will not have time to ripen.

For better results storing them, allow winter squash and pumpkins to thoroughly ripen before harvesting.  And remember, once harvested, to keep them in a cool but not cold place.

As each vegetable finishes producing, remove the plants from the garden in order to prevent diseases or pests from wintering over in the old foliage.  Sowing winter (or ‘annual’) rye will provide roots to stop erosion of uncovered soil, and when turned over in the spring, it will add nutrients and biomass to the garden.

September is the perfect month to divide perennials, like this hosta

In the Flower Garden.  Autumn is a great time to divide and plant many perennials.  If your perennials have finished blooming, consider digging and dividing them.  Everything from peonies to bleeding hearts can benefit by creating divisions of the ‘mother’ plant.  As you plant, make certain to put divisions into ground at the proper depth—exactly as deep as they were growing before.  And enrich the soil with compost or well-aged manure to give the roots a great start. Don’t allow the new plantings to dry out, and don’t mulch the area until cooler temperatures arrive.

Bachelor Buttons can be planted in the fall to get a jump on Spring 2018

And you can plant seeds now!  Some flowers (such as bachelor buttons) do better if they are planted in the fall (the way Mother Nature would) and allowed to winter over.  In the spring you will have a serious jump on those only putting their seeds in the ground meaning stronger, earlier flowers next summer.

September is the month to plant all narcissus (daffodils) as well as smaller bulbs.  Don’t plant tulips until the end of the month.  And remember, while deer and rabbits love tulips, they generally ignore daffodils and hyacinths.

September is the right month to reseed bare spots in a lawn

Lawns.  September is the best month to establish new lawns, feed your lawn, or deal with bare spots or thin grass in established lawns. Grass seeds face virtually no competition if planted in the fall because grass is a cool season plant, but most annual weeds are not.  Existing lawns should be mowed short and raked thoroughly before reseeding.  Water new or reseeded lawns as needed to prevent the seed from drying out before it develops mature roots.  Do not mow or rake again until the new grass has established strong enough roots not to be pulled out. Feed lawns but do not put down weed killer now—the weeds are already dying as the days get cooler.

Controlling invasive knotweed can seem overwhelming, but doing nothing about it is worse.

Invasives Alert I.  A really bad guy, Japanese Knotweed was brought to this country as a decorative plant, but it also a terrible thug.  It spreads by seed but also by underground rhizomes.  Because of its ability to root from cut canes (!), always bag all parts of knotweed and send it to your local transfer station.  After you’ve cleared an area, make a note to go back in a month to six weeks, where you’ll find the knotweed thriving again.  Keep repeating the cut-and-bag process because it takes at least four cuttings to kill the underground rhizomes.   Why bother?  Because knotweed is bad for the environment.  It crowds out native plants that native birds and animals depend on.

Swallowwort seed heads are maturing. If you see it, cut it, and take it somewhere it will be incinerated.

Invasives Alert II.  Black swallowwort is one terrible invader.  And it’s about to send it’s seeds out into the world.  Distantly related to milkweed, it can be mistaken for the only plant that is a nursery to Monarch butterfly larva.  The female Monarch butterfly thinks she’s laying her eggs on the perfect host, is instead laying them on a plant that will kill the caterpillars soon after they hatch.  Please look around your home, the areas where you walk, your town parks (some was growing in a bed at my local Library!) and pull it out.  Too much to pull—then take clippers and a bag and cut off the seed heads, bag them, tie it securely and send them to your local dump.  Never compost any part of the plant.

Additional Hints from Previous Years: September 2016


Drought Monitor August 30, 2016In eastern New England, this has been a summer to remember… for its drought and heat, which inevitably lead to watering bans in communities from Maine to Connecticut.  The map at right tells the story: ‘Extreme Drought’ covering a swath of land encompassing all of Greater Boston and extending up into southeastern New Hampshire, with the rest of New England experiencing drought conditions ranging from ‘Moderate’ to ‘Severe’.  It has been more than 20 years since we’ve seen things this dry.

But there’s a lesson in that drought: never take water for granted and, unless it has soap or chemicals in it, don’t let it go down the drain.  At my home, we kept a two-gallon buckets in the shower to capture that first surge of cold water that precedes the warmer temperature under which we bathed.  We kept jugs under the air conditioning condenser drains and collected several gallons of water that day.  Vegetables were washed into dish tubs, resulting in another few gallons every day.  Our four rain barrels also collected rainwater – on the few days there was precipitation.  We also planted for minimal water use.  There’s no lawn at our new home, and our focus for planting is on tough, drought-tolerant natives.

Maybe 2017 will be a ‘normal’ summer by New England standards but, if it isn’t, we’re prepared.

Topping your tomato vines at the beginning of September will make the plant put its energy into ripening fruit

Topping your tomato vines at the beginning of September will make the plant put its energy into ripening fruit

Top your tomatoes. Most varieties of tomatoes are ‘indeterminate’, meaning the vines that will keep growing until killed by frost.  By cutting off the top of your tomato plants down to where fruit has already set, you encourage the plant to put its energy into ripening the fruit already on the vine rather than generating new leaves and flowers.

Check those leftover seeds!

Check those leftover seeds!

Enjoy vegetables this fall.  It’s not too late to plant some vegetables for fall harvest.  Start by inventorying your leftover seeds.  Do you have peas, spinach or lettuce?  Plant them now; they have plenty of time to produce a crop.  How about Tokyo turnips?  They are ready to harvest in a month.  Read your seed packages with an eye to ‘days to maturity’ then count back from the first frost date, mid-October for most of us.  .

Row covers are back in fashion.  The row covers you used in May and June to keep out bean beetles and other bad bugs can be pulled out again, this time to provide a few degrees of nighttime protection against cold.  Check your town’s swap area for a hard plastic or glass covers (old doors or windows work well) to give you a simple cold frame that can keep your garden growing until covered with snow.   You can add 60 days or more to your growing season.

Diseases like leaf mold on this tomato plant make it a candidate for the dump, not the compost pile

Diseases like leaf mold on this tomato plant make it a candidate for the dump, not the compost pile

What to compost, what to bag and discard.  As you remove spent plants from your vegetable garden, look at each one with a critical eye.  Send any plant that is either diseased or infested with bugs to the dump.  Compost the clean plant material to create ‘Black Gold’ for next year’s garden.

Pull out crabgrass before it has time to spread its seeds

Pull out crabgrass before it has time to spread its seeds

Clean up your yard.  Take advantage of cooler mornings and evenings to do the weeding we avoided in August.  If it seems like weeds were the only thing that managed to grow during the drought, it isn’t an illusion.  Weeds such as crabgrass thrive in dry soils.  Reward that hardiness with a good tug and a trip to the dump.  Every weed that goes to seed means many more to deal with next year.

Don't be in a hurry to rake the leaves that collect under shrubs

Don’t be in a hurry to rake the leaves that collect under shrubs

Think twice before you rake.  While cleaning your yard remember the leaves that fall are food for the plants.  Use a mulching mower to chop up the ones on the lawn.  They will finish disintegrating over the winter.  Under bushes and around perennial beds, fallen leaves serve as a winter mulch and a home for many beneficial insects like butterfly caterpillar so please don’t chop them and leave them be.

Freshen up your containers for fall with heucheras and grasses - not mums

Freshen up your containers for fall with heucheras and grasses – not mums

Freshen your containers.  It has been a tough summer for plants in containers.  The unrelenting heat and the regular dousing with chlorinated tap water (in place of the non-existent rain) is not conducive to a long happy life for your annuals.  It’s too early to use cut evergreens, so consider putting in some transitional plantings such as the multi-colored kale, perennial grasses and heuchera.  Avoid using mums.  They aren’t a good choice if you like to keep the season going until Thanksgiving because the flowers will die long before that.

September is the perfect month to divide perennials, like this hostaDivide and multiply.  September and October are great months to dig and divide overgrown perennials that bloom early.  Creeping phlox, oriental poppies, foxglove, delphinium and iris are all candidates.  You can also dig and divide later blooming plants such as hostas and many ground covers.  Spread them around your property, share them with friends or pot them up for your garden club’s spring plant sale.  They will be healthier and look better if you don’t wait until spring.

Grass is a tough perennial. It will turn green with cooler weather

Grass is a tough perennial. It will turn green with cooler weather

Benign neglect for your lawn.  The summer heat and water bans have been tough on everyone’s lawns, but don’t try to rehab them this autumn unless Mother Nature suddenly provides us with lots of rain and the watering bans are ended.  Apart from pulling crabgrass and other obvious weeds before they set seed, leave your lawn be. Grass is a hardy, cool-weather perennial, and there are steps you can take later this autumn and next spring to enhance your lawn.

Planting bulbs too soon may cause them to begin growing tops

Planting bulbs too soon may cause them to begin growing tops

Spring bulbs.  Wait until the soil temperature has dropped to 55 to 60 degrees several inches below the surface to plant spring bulbs.  This usually occurs after several weeks of nighttime temperatures in the low 50’s.  Putting bulbs into warmer soil may cause them to begin growing tops (which is bad) when they should be growing only roots to support the flowers next spring.   Now is also a good time to dig up any bulbs that have been in for a few years. You’ll likely find they’ve multiplied and are now crowded (yeah! free bulbs) and need to be thinned; or have been attacked by moles, voles and other varmints and need to be replaced.  Add lime over old and new bulbs now, but fertilize only after they are in bloom in the spring.

Hints from earlier Septembers:

Take Pictures, Make Plans.  If your garden is perfect, take its picture.  If your garden is looking tired, take its picture.  If your garden doesn’t make you happy, take its picture.  If you do this once a month through the spring, summer and fall, you have the information to help figure out why your garden is perfect, tired or not making you happy.  By analyzing those photos you can see where you need to add more spring bulbs, late summer plants or shrubs and trees to provide structure to your garden throughout the year.  Didn’t take any photos in the spring? Start now. And don’t forget to take some in the winter!  Only by looking at your successes and failures can you make plans for the garden that doesn’t disappoint.  Whether you do your own landscaping, or have someone do it for you, it’ll be more successful when you can point out what you like or dislike about the garden you have now.

Don't be worried about mushrooms on your lawn

Don’t be worried about mushrooms on your lawn

Clean-up Time. It’s time to start cleaning your gardens.  As plants reach the end of their life (annuals and most vegetables), cut them down and add the healthy material to the compost bin.  Any diseased (for example, downy mildew) or insect-infested material should be bagged and put in the trash.  Weeds should be cleaned out now because, left to their own devices, they will plant hundreds of thousands of seeds in your lawn and garden, making your job so much more difficult next year.

If you find mushrooms in your lawn or garden, leave them alone because they help break down organic matter.  Forget fungicides and simply knock them down with a rake if you are annoyed by the sight of them.

A cold frame will allow you to pick vegetables into November or December

A cold frame will allow you to pick vegetables into November or December

Fall Planting — Vegetable.  It’s not too late to be planting in the vegetable garden.  Add more lettuce, radishes, oriental greens, Tokyo Cross turnips and quick maturing beets.  If we have a mild fall, you may be picking through October or even into November.  Want to stretch that season?  Build a simple cold frame that will keep cold weather vegetables growing through December or until it is covered with snow. Or at least put a double layer of row cover over your fall crops when frost is expected.

If some of your garden has emptied out, plant oat seed as a cover crop in those areas.  The oat plants will die when hit by hard frost, having reduced weeds, recycled nutrients and prevent erosion.  In the spring the dead plants are easily turned over or even planted through.

Early September is the time to trim back the growing ends of your tomato plants

Early September is the time to trim back the growing ends of your tomato plants

And while it is strange to write this as the thermometer reads 90 degrees, it’s time to tell some plants to stop producing and concentrate on ripening. Around Labor Day, I cut the growing tips off tomatoes and winter squash.  There is very little chance they will manage to put out new flowers, grow the pollinated flowers into squash or tomatoes that will ripen before that first real frost.  I want my plants to concentrate on putting all their energies into growing and ripening the tiny green tomatoes into large red slicing tomatoes and the similarly small and greenish winter squash into large, brown winter squash for my Thanksgiving and Christmas table.

Watering.  This has not been a good year for the water-conscious gardener.  It has been dry and hot, hot and dry.  The rain came in bursts and then disappeared for weeks on end. Water bans throughout the area has made watering plants very difficult.

It is important to remember to water newly planted trees and shrubs right up to December, or until the ground freezes.  Don’t put fertilizer on any plant, including grass, unless it is raining outside or you can give it a deep soaking.  Fertilizers are salts that will burn the roots if applied to dry soil.

The journal entries you make this month will help you garden for years to come!

The journal entries you make this month will help you garden for years to come!

Your garden journal. This has been an unusual summer – drier and decidedly cooler than most. How did your garden fare? What needed the most watering? What vegetables did best, and worst in this weather? What would you give another chance because it was a cool summer? What’s off your grow list for next year?

If you kept up your garden journal – making even one or two entries a week – you could easily answer those questions. If not, take an hour today and write down what you remember, and what you’d rather forget. It will help you next year and in future years to make your garden better – and perhaps your work a little easier.

* * * * *

Put away your pruners, for now. This is not the time to be pruning any woody plants around your garden. Spring blooming trees and shrubs have set their flowers for next spring, so pruning would remove those buds. As to those still blooming (or recently finished), pruning them now will encourage new growth that will likely be too tender to make it through the winter. Pruners and saws should not be used on woody plants until the cold weather is thoroughly established in November.

* * * * *

Weeding isn't just a spring and summer thing

Weeding isn’t just a spring and summer thing

Keep weeding! Weeds are setting seeds in every area of our gardens now. They want to be ready for next season. To save yourself extra work in the spring and summer, remove weeds now. Start with any that are in flower or have seed pods. Pull or dig them out and put them in the trash (composting weeds can lead to weed seeds with a great head start!).

* * * * *

Fertilize your grass in the autumn (courtesy Cornell University)

Fertilize your grass in the autumn (courtesy Cornell University)

Lawn renewal. Now is the best time to begin renewing your lawn, or installing a new one. In the fall the temperatures are cooler (the grasses we grow for lawns come from areas without our hot summers) and there is usually more rain. Even more good news, most weeds will not germinate as the days get shorter, which means your lawn get a good start before it faces competition from plants you don’t want to grow.

An ideal time to fertilize is between Halloween and Thanksgiving – about two weeks after your last mowing. Apply one pound of 70% slow-release nitrogen fertilizer per 1,000 square feet. That almost always means an organic fertilizer. Are they more expensive? Yes. Will they do a better job? Also yes.

A late fertilizer application helps the plants build up reserves to get through the winter and green up healthfully in spring. That’s because top growth stops in fall after about ten days with average daily temperatures below 50° F. Roots, on the other hand, will continue to grow and take up fertilizer until the ground freezes.

* * * * *

If your tomatoes have been stricken by late blight, be sure to remove every trace of the affected plants.

If your tomatoes have been stricken by late blight, be sure to remove every trace of the affected plants.

In the vegetable garden. While your vegetable garden may be slowing down, you still have a lot to do. If you planted lettuce, spinach, Swiss chard and beets last month, there will be food to harvest until a heavy frost (below 28°) or even closer to 20° if you cover the plants at night with row covers or old blankets. Don’t use plastic as it readily transfers cold to the leaves it touches.

As crops finish their season, clean the beds thoroughly. This year, late blight again made its ugly presence known in Massachusetts garden. Tomato and potato plants infected with blight need to be bagged and sent to the trash. This includes fruit that fell from the vine before ripening as well as dead leaves. As a general rule, it is much better to be safe by sending any plant material from your garden that was insect- or disease-infected to the dump rather than the compost heap.

September is hurricane seasons in the Northeast. Prune trees to keep them 'airy': the wind should blow through a tree, not topple it.

September is hurricane seasons in the Northeast. Prune trees to keep them ‘airy’: the wind should blow through a tree, not topple it.

Hurricanes sound exciting… right up until they hit.  Some areas of New England suffered greatly last year from Sandy’s fury, but even those of us not along the shore are susceptible to damage from the winds and rain.  September is hurricane season in the Northeast and now is the time to survey your property.  Trees should be pruned if they are too densely packed with branches and leaves.  A thinner canopy allows wind to blow through.  Diseased and dead wood should always be cleared out, but also look for trees too close to your house or overhanging buildings, parking areas or electrical wires.   Call in a certified arborist to do the work, don’t try to handle anything you can’t reach from the ground yourself.

Nurseries want to go into the winter months with their stock at low levels. Bargains abound, but plant carefully.

Nurseries want to go into the winter months with their stock at low levels. Bargains abound, but plant carefully.

Trees & Shrubs.  It’s a great time to buy and plant new trees and shrubs if you remember two things.  One, the selection may be limited and buying something that doesn’t fit your needs (or space) isn’t a bargain.  Second, the plants you buy now have likely been in the nursery all summer.  Plant correctly – removing all wrappings, spreading out roots in the hole, even if you have to break a few roots to do so, planting no deeper than the flare of the plants and  watering new plantings until the ground freezes.  After the ground has started to freeze, add a layer of mulch, not for protection from the cold, but from warm spells, which are more dangerous to the newly planted in the winter.

Vegetable Garden.  Last call to plant lettuce, spinach, oriental greens, quick turnips ( like Tokyo Cross) in the ground.  Pull root crops carrots, beets and such only as you need them.  A light frost will not hurt them.  If you have a cold frame, plant it now also.  With a little luck you will have fresh vegetables for your Thanksgiving, Christmas and New Year’s dinners.

If our dry weather continues, don’t forget to water ongoing crops to keep them producing.   And water strawberry plants. They are now setting the buds that will become next year’s berries, but they can’t do that if they are suffering with dry conditions.

If our dry weather continues, keep watering your vegetable garden until it's time to call it a season.

If our dry weather continues, keep watering your vegetable garden until it’s time to call it a season.

Once an area of the garden is empty of crops, do a thorough clean-up removing (to the dump, not the compost pile) any plant material that may have been infected by disease or insects.  Corn borers will winter over in corn stalks and tomato diseases live on in the soil.  Once the area is clean, consider putting in a cover crop of annual rye, oats or professional mixes designed to add nutrients and organic matter to the soil when you turn them under in the spring.

When the vegetable garden is finished for the year, a layer of half-composted manure from cows, sheep, horses, chickens or other vegetarians can be placed directly on the garden.  Winter sun and cold, rain and snow will finish aging the manure so it is ready to be planted in next spring.   Manure applied in the spring should not be planted in for at least one month because “fresh’ manure can burn seedlings with excessive nitrogen.

Insects.  It would seem with the end of the growing season approaching, insects would be less of a problem, but that is not always the case.  Wasps, including the yellow jackets that are often misidentified as bees, are particularly aggressive.  Beware of hives in trees, shrubs and in the ground.

Insects become aggressive as the season winds down. Yellowjackets are especially a problem, and always be wary of ticks.

Insects become aggressive as the season winds down. Yellowjackets are especially a problem, and always be wary of ticks.

Snails and slugs continue to mar hostas and other susceptible plants (I found a snail this weekend on a branch of a leopard lily ( Iris domestica) five feet above the ground). Kill them now with an iron phosphate based product (such as Sluggo) which, unlike older remedies, is harmless to pets, other wildlife and the environment.  When cleaning your garden, remove and destroy all potentially infected plant debris because slugs leave behind eggs to hatch next spring.

Be on the lookout for Asian long-horned beetles or signs of their activity.  Perfectly round, dime sized holes in the trunk of maples, birches and other hardwood trees indicated their presence.  Report any suspected infestations to www.massnrc.org/pests/albreport.

And beware of ticks, they continue to be active even as the temperatures drop.  The list of tick-borne diseases grows each year.  Moreover, ticks do not die with the first frost: they survive to hop onto the unwary any day the temperature is above freezing.

Outdoor gardening

Start your fall planting now.  The weather is cooler, the plants are on sale and you know what you fell in love with in other gardens this summer.  Because they’re free to direct their energy to creating roots rather than leaves; trees, shrubs and perennials all do well when set out in the fall.  Be certain to plant properly (here’s a good article on the subject).  Keep your new plants well-watered until the soil freezes.

When a perennial has a dead center like this, it’s time to divide it

It’s also a great time to dig up and divide perennials that are getting tired (a dead spot in the middle of irises, a lack of bloom on older plants).  Allow fall-blooming perennials to continue to shine, but just about all others will thrive if replanted in fresh soil amended with compost, are watered until the ground freezes (probably early December) and mulched with two or three inches of fresh mulch to keep the ground from thawing out with each warm day in the winter.  Hardy plants aren’t killed by freezing weather; they succumb when warm days thaw the soil, heaving their roots out of the ground.

If you haven’t already, order bulbs or buy them at local nurseries for the best selections.  While you can begin planting narcissus (daffodils) now, wait until the soil cools in October before planting most spring bulbs.  Don’t forget to buy extras for forcing during the winter months.

Lawn care

September is a good time to fertilize or lime your lawn but before you do, have a soil test done if you didn’t do one in the spring.  Click hereto reach the UMass soil test lab, which offers a very low-cost service for homeowners.   Only add fertilizer if the test indicates the lawn needs it.  Like too much of anything, too much fertilizer will make a sick lawn sicker.

Dig out the soil from under areas of dead grass

Do you have bare spots, thin lawn, or too many weeds?  Now is the time to deal with these problems.  If the dog likes one area too much or if the kids preferred one spot for home plate, dig out the soil under the dead grass to create a hole 6 to 12 inches deep.  Replace the depleted dirt with fresh soil amended with compost.  Tamp it down, add high quality seed and water once or twice daily for two weeks or until you see grass blades several inches tall.

It’s too late to do anything about crabgrass except to limit the number of seeds it leaves behind.  The best solution for crabgrass is to physically remove it — by hand if there are only scattered patches, or by digging it up if it covers large areas.  Attack broadleaf weeds that winter over such as dandelions and ground ivy now so you will start with a better lawn in the spring.  But remember that weed-and-feed products also kill clover which was always a part of a healthy American lawn until broad-leaf herbicides began being marketed in the 1950’s.  Clover stays green in droughts, adds nitrogen to the soil and is resistant to many insects and disease that wreak havoc on your lawn.  Give clover a chance, add it to any grass mixtures you use to overseed your lawn.


Indoor gardening

Inspect houseplants that have summered outdoor for insects and diseases

Time to begin the process of moving houseplants inside for the winter.  Start by re-potting plants using a fresh potting mix. This step will help eliminate insects you might have picked up, particularly if your plants have been sitting on the ground.  Examine all houseplants closely for insects or disease, including those who resided on porches or decks.  A water spray will remove dust, pollen and many hitchhikers from the plants.  If the pests reappear, spray with an organic insecticide or decide whether you can live without that plant rather than risk introducing pests into the house.  Stop fertilizing houseplants now—they will naturally grow more slowly in the winter.

Rather than bringing plant directly indoors – an abrupt move that can shock a houseplant – move them first to more protected and shadier areas to prepare them to come inside.  All plants should be back indoors before October 1.



These leaves are waiting to be moved into your lawn to make next year’s fertilizer

Raking–Don’t! Research by Cornell Extension Service shows that raking your lawn is totally unnecessary. Just use a mulching mower (almost any gas or electric-powered mower will do) to chop the leaves into small pieces which will compost directly into the soil over the winter. Cornell’s research shows that even sixteen (16!) inches of dried leaves can be added to the soil every year. This includes tough oak leaves, which break down very slowly unless they have been chopped up, and pine needles, which are less acidic than oak leaves. If your leaves are deep, you may have to mow twice to chop them all sufficiently small, but it’s still a lot less work than raking and much better for the environment than throwing leaves in the trash. By mulching, all the nutrients used to grow the leaves go right back into the soil where they’ll be available for the tree roots to take them up for future years.

In the vegetable garden. It’s time to start the clean-up while still enjoying the produce. You should be able to harvest tomatoes, squash and green beans well into September. Mid-summer plantings of lettuce, beets, carrots and chard will keep producing even though a light frost. When harvesting winter squash, be certain to leave an inch of stem so it can be stored successfully.

Make your final clean up easier by removing crops as they finish producing. If you had disease problems with tomatoes or squash (or anything else), bag and remove the plants not just from the garden but all the way to your local dump. If you leave diseased plants in place, you’re starting next spring with extra trouble brewing in the soil. If you have bare soil when your garden is finished for the season, a planting of annual rye will act as a cover crop, preventing erosion even after it dies back in the winter. The rye will also add organic matter for next summer. Cover crops aren’t just for in-ground gardens; they work well in raised beds as well.

Bringing in houseplant and saving annuals. It’s time to begin moving houseplants back into the house. One cold night can kill most of the tropicals that we allow to ‘summer’ outdoors. Moreover, if you move them now from full sun to part sun, the move indoors where light levels are much lower will be that much less traumatic.

If you have annuals you want to save, now is the time to take cuttings and start new plants. Everything from coleus to geraniums can be rooted and be a houseplant for the winter. Take small cuttings, about four inches, from the growing tips of a healthy plant. Remove all except the top two leaves and insert the cutting about one inch into sterile medium such as perlite, vermiculite or coarse sand. You may use a root hormone but it is not necessary to get good results with most annuals. Water the ‘soil’ until it runs through the container, then cover it with a clean plastic bag, place it in bright light but out of direct sunlight and wait until you see growth begin on the root tips. In four to six weeks, your cutting should have sufficient roots to move to a new pot and you’ll have a new houseplant.

Cleaning up Flower Beds. Whether you prefer a fall or spring clean-up, it’s important to remove any diseased plant material now. Our wet spring and hot July seemed a perfect recipe for mildew in my own garden. Remember to sharpen your cutting tools before beginning. Dull blades tear plant material and allow insects and disease easy entry. When cutting down a plant with mildew, or any fungal disease, practice good sanitation. Keep a container of bleach with you and dip your shears or pruners in the bleach before each cut. It may sound like extra work, but preventing the spread of disease will save you much more time and effort than it takes to make the quick dip. Get in the habit and you won’t accidentally use the ‘dirty’ pruner to cut an uninfected plant. Disease can travel down stems and winter over in the roots, ready to attack in the spring. Put the diseased plant material in separate containers from the clean, compostable material. Then take the diseased material to your dump or transfer station where it won’t become part of next year’s garden. Only clean – disease-free and pest-free – plant material belongs in your compost bin.

Lawn reseeding and general maintenance. Those of you who read this column regularly know I am not a fan of large lawns. But if you are going to have one, now is the time to put in the work to make it better next summer. Most weeds that homeowners want out of their lawns are annuals. Any that might pop up while you rehab your lawn now won’t be here to bother you in the spring. Reseeding, also known as overseeding adds new grass plants to your existing lawn. The more grass, the less room for weeds. If you are like me and don’t enjoy extra work or chemicals, consider adding clover seed, a traditional part of the home lawn. Clover takes nitrogen (the largest part of any lawn fertilizer) from the air and puts it in the ground in a form available to its neighbors, such as your grass. Clover seed is available at farm stores and some nurseries.

Invest in good seed – cheap seed may contain annual grass seed which will die over the winter (not the perennial seed you want), or even weed seeds! Make certain you buy seed appropriate for the area: sunny, shady, play area etc. Remember that no grass will grow well in areas where you get less than four hours of sun a day. You’re much better off using your money to buy a shade-tolerant ground cover.

If you haven’t aerated your lawn in several years, it may need it. Do the aeration, then seed.

Once you have seeded, you must water daily for a couple of weeks. With the ground saturated right now (thank you, Irene), you should not have difficulty keeping the seed moist enough to germinate.

If you have access to compost, spread the seed and add a thin (1/4 inch) layer of compost over the top. It will disappear quickly while providing a healthy start for your seed.

Summer vacation is ending for your houseplants. While it is still very warm outside, houseplants need to begin the transition back into your home. Any that have spent the summer outdoors should be brought onto a porch or deck where they receive less daylight, a step to help them acclimate to the lower light level in your home. Plants that have been in contact with the ground should be repotted to ensure worms, ants or pests are not tagging along. Check for any obvious signs of insects on the leaves, stems and top of the soil. A strong spritz from the garden hose followed by spray of insecticidal soap can help to keep aphids mites and others from causing a big problem indoors.

Once you make the move indoors, don’t despair if your plants drop a few leaves. The drier air and lower light levels mean the plant cannot support all the foliage it did outdoors. Many plants will replace the leaves after they have readapted.

It’s a great time to take cuttings from some tender favorites such as begonia, coleus and geranium. Cut a 4-inch tip of the plant, remove the largest leaves, dip in rooting hormone and place in wet sand or a perlite/peat moss mixture. Keep this growing medium wet until a gentle tug proves that roots are in place. Then, transplant to a small pot and you have a new houseplant. In a southern window you may even get blooms.

Finally, start thinking about the Amateur Horticulture competition at the 2011 Flower Show. Last year’s schedule is still available (click here). Next March will look bright with a shiny ribbon on your plant!

Planting for fall/winter It’s been a long hot summer and the last thing some of us are thinking is planting at this time of year. But it might be a good idea to reconsider. We can see where our garden needs a boost. It is easy to plan a spring and summer garden; harder to think ahead to where we need color or structure for the fall and winter months. Nurseries are full of plants that can offer exactly that, and they’re likely on sale.

I am not a fan of chrysanthemums for fall. The colors are too brassy, the plants too short lived. I leave annuals in place until they are killed by frosts (usually the same time that the mums would be killed) and supplement them with perennials that will provide color throughout the winter. Heuchera are wonderful plants that show off their colorful leaves year round (when not buried under snow). Those not watered may have suffered this summer, but cutting back dead leaves will lead to fresh replacements. In shady areas, plant epimediums, which keep their greenery throughout the winter and add flowers to the shade in the spring.

And don’t forget trees and shrubs. It is not too late to plant as long as you water consistently until the ground freezes in December. Trees add not just height but also interesting bark and structure after the leaves are gone. Evergreens add priceless greens, blues and yellows to the winter landscape. Shrubs provide offer color, bark, berries and shelter for the birds.

Don’t rake! Take a look at the forest floor: it is covered with leaves. They provide the only nutrients that the native trees get. They are the mulch that protects the roots and new seedlings. Traditionally, we rake to remove leaves that would otherwise smother our lawn over the winter. But with a mulching mower you eliminate one time consuming chore. Always mow your lawn using a mulching blade on your mower. This returns finely cut grass clippings to the lawn. In the autumn, the same blade will chop leaves into small pieces. These pieces will not mat. Instead, they’ll break down over the winter, returning the nutrients to the soil in the process. In October, if the leaves are particularly thick, you may have to go over an area twice, but this is still substantially less work than raking.

In flower beds and under trees and shrubs, leaves can remain for the winter to help protect the roots and crowns of your plants. Cleaning them out is a spring chore.

Mushrooms in the lawn? After a horribly dry summer, we had 4 days of rain in late August and await a hurricane this week. The result may be the sudden appearance of mushrooms of all sorts in your lawn. If the sight of mushrooms sends you looking for a cure… stop. Those mushrooms are a sign of organic material decomposing under your lawn, which is a good thing. While I strongly advise against eating them unless you are an experienced mycologist, enjoy their unusual shapes and colors. And, if they bother you, just kick them over.

Put in your spring and summer bulb order. Bulb catalogs have been arriving all summer. Now, sit down and decide what you need to brighten your garden next year. Ordering now means a wider choice of varieties than are available at most nurseries. Consider adding the early and less-well-known bulbs such as Chionodoxa, Camassia, Pushkinia and others.

Need to redo your lawn? Now’s the time. Grass grows best in the cooler temperatures of autumn and annual weeds are not a problem now. Whether overseeding or starting over, get a soil test, so you know how much lime and fertilizer are needed before you begin. And while you are doing that work, consider if some part of what is now lawn wouldn’t be better as a tree or shrub bed. It would reduce you future work and add more interest to your property.

Daylilies are true workhorses but, like many other perennials, they cannot go on forever without some care. Daylilies need to be dug up and divided every three to four years to keep the plants youthful, and September is a great time for this chore. For the sake of convenience and because they’ll have fewer roots when you are finished, first cut the foliage in half. Shake or wash most of the dirt off the roots. Daylily roots are tough and you’ll need a pair of spading forks or a sharp shovel to break apart the mass. Discard the old center and replant divisions that are 6 to 8 inches across. Too many plants? Share them with friends, just remember to make note of the blossom color when potting them up.

In the vegetable garden, many tomatoes, which usually have buried us with their bounty by now, are struggling along because of the blight spread by seedlings from the big box stores this spring. Weakened by the loss of foliage, the plants may have set fewer fruit or produced smaller specimens. If you had blight, be certain to remove the plants from the garden, have them taken away with household trash (do not compost them under any circumstances!), and try not to plant tomatoes in that area for several years until the fungal spores have died off. Start your own seedlings or buy them from reputable local nurseries. This will reduce the chance of introducing more diseases into your garden.

Winter squash and pumpkins are ripening on the vine now. Do not pick pumpkins until they have turned uniformly orange. When picking winter squash always cut the squash from the vine leaving at least two inches of stem attached. This makes the squash less likely to rot in storage. Wash the picked, undamaged squash in a ten percent bleach solution and then allow them to dry in the sun for a couple of days. They will keep in a cool dry room for months providing a dish from your garden long after it is buried in snow.

If a light frost is predicted this month, cover plants you’d like to continue enjoying. Tender annuals and hot weather vegetables can be covered with large garbage bags or old sheets. Just remember to remove the coverings in the morning. If hard frosts hold off into October you will have the pleasure of a few more weeks of fresh vegetables and a colorful garden or containers.

 Posted by at 9:44 pm