Invasives Strike Force

Today I received my year-end newsletter about the Invasives Strike Force, a project that my husband and I have participated in since its inception (as a Rutgers research project) in the mid-2000s. This year, the ISF monitored over 260 miles of trails in the NY-NJ region for invasive plants. Visit the ISF website for information about the important work the group does in monitoring trails and removing invasive species, as well as to find out how you can become involved in this effort. You can also view photos and a description of the hike my husband and I did this year to monitor for invasives here.

 

Plant a prairie

Prairies (or meadows, to use the European term) are extremely diverse assemblages of flowering perennials and grasses. They are beautiful from spring to fall, and the seeds they produce feed the birds all winter. In this area prairies were always interim ecosystems—in a place where the forest canopy was destroyed by fire or flood or the activities of humans, a small prairie would appear and would remain for several decades until the woody growth took over.

I have three small prairies—most people would call them perennial borders. Each is four or five feet wide and up to thirty feet long. The picture above shows part of one of these gardens in June; the picture below shows a different one in August. They contain a wide variety of native flowering perennials and grasses. Two of these plots were planted around 15 years ago, one was begun about 8 years ago but has been extended several times. They have never received any fertilizers, chemicals, or soil amendment, and they are watered perhaps once or twice a season, if there’s a particularly dry spell. They provide glorious bloom from May through October and seedheads that feed the birds all winter.

You can start a prairie garden from seed (fairly difficult) or from plants (very easy). To start from plants, choose a site that gets full sun. Select plants that are well-adapted to your site, particularly in terms of whether it’s wet or dry, sunny or shady. To remove the existing lawn, you can do several different things, but the easiest is just to apply a thick (3-4”) layer of mulch, such as shredded hemlock bark. Lay the mulch down in fall and the ground will be ready to plant in spring. Plant right through the mulch. Do not amend the soil in any way.

When ordering plants, allow approximately one plant per square foot (so for a garden that is 4 feet wide by 20 feet long, you would need 4 x 20 or approximately 80 plants). As you select plants, be sure to consider height—some prairie species can grow 8 feet tall, and you probably don’t want too many of those in a small space. Choose plants of varying heights and bloom times, and be sure to select a mixture of flowering perennials and native grasses. In nature, forbs (flowering plants) and grasses always grow together; the grasses are beautiful year-round and the backbone of the prairie ecosystem. Grasses, like flowers, attract birds and butterflies, and their root structure complements the roots of the perennials so that the plants keep each other from flopping over.

Spring is the best time to plant. Once the plants are in the ground, water the garden thoroughly and keep it watered whenever there’s a dry spell during the first growing season. Some plants will be slow to take off, but some will bloom that first season. By the second season, and certainly by the third, the garden will be spectacular. You will be astounded by the variety of pollinators, butterflies, and birds it attracts.

A couple of details of care are radically different from everything you’ve ever been taught about perennial gardens. First, do not use any fertilizer or soil amendments—ever. Prairie plants are tough, and they build their own soil. Second, do not do any garden cleanup in the fall. Butterflies and other helpful insects will overwinter on the ground in the leaf litter, and birds will eat the seeds all winter.

Each spring, remove the previous season’s top growth, breaking down the tough stalks close to the soil level (they will snap off very easily). Once everything is on the ground, rake away the litter and either compost it yourself or take it to the town recycling center. That is the only maintenance involved.

Take some time this cold, snowy weekend to plan next year’s prairie garden.

Plant a forest

This is my backyard forest. We planted it about 18 years ago, and this picture was taken about 10 years after it was planted. Northeastern North America was once entirely covered by forests, interspersed with meadows on very wet, very dry, or recently burned sites. Any piece of ground left to itself quickly reverts to forest. So forests are the easiest type of ecosystem to create and maintain—basically, remove invasives and enjoy (as you continue to monitor and remove invasive species). From an ecological point of view, forests are also the best ecosytem you can maintain: the most friendly to wildlife, the most protective of our air and water. Once established, forests grow and change but remain for a long, long time. They are the definition of sustainability.

A forest doesn’t have to be large. Perhaps you have an unused strip of ground a couple of feet wide along the edge of your property. Stop mowing it. Within a few weeks the grass will grow long and wildflowers such as lobelia, asters, goldenrod, and milkweed will spring up. Within the first growing season woody growth will appear—native sassafras, black cherries, and oaks, but also invasives such as Norway maples and multiflora rose, depending on what’s growing around you. Pull out the invasives and allow the natives to grow. In just a few years, you will have a little strip of woodland, complete with woody plants and understory flowering plants and grasses. If you like, you can plant additional species such as ferns beneath the trees, or you can add once-common shrubs such as serviceberry, which birds adore. You will have a productive ecosystem that provides food and cover for wildlife year-round where you once had waste ground.

A forest can occupy any part of your property that is now unused. For example, leave the center of your backyard as lawn but plant trees and shrubs all around the perimeter. Or plant additional trees and shrubs around a specimen tree on the front lawn. Or join two or three widely spaced specimen trees with shrubs, vines, and groundcover. My forest stretches across the back half of our backyard. It was formerly lawn.

Start your forest with free plants—use what grows—or purchase trees and shrubs. My forest now contains a combination of plants we bought and plants that have appeared over time–volunteers. Choose fast-growing species and you’ll have a beautiful native ecosystem within five years. Whatever native species you choose, you will have improved your local environment for many years to come.

Some gardening books

The picture above shows part of the native forest that stretches across out modest suburban backyard. Notice the flowering dogwood and the white ash in the background that was just leafing out in mid-May. Everuthing you see was planted by me and my husband, and this lovely woodland replaces a very boring bit of lawn.

This photo encapsulates my approach to gardening, which, as my regular readers understand, is to attempt to restore the natural environment. This approach is not ornamental so much as ecological (although I think the results are very beautiful). I plant native plants and I choose plants that are well suited to my site. I try to work with nature rather than to impose my will on my tiny slice of the environment. If this approach is of interest to you or to your gardening friends, here are some books that you might consider getting for yourself or for gifts.

Noah’s Garden  and Planting Noah’s Garden, by Sarah Stein

These two beautifully written books, taken together, tell you everything you need to know about environmental gardening—what it is and how to do it here in the Northeast. Noah’s Garden tells you why, and Planting Noah’s Garden tells you how. These books are out of print but still available on amazon.com.

Native Alternatives to Invasive Plants (Brooklyn Botanic Garden Guides for a Greener Planet)

The book that answers the question “What should I plant instead?” Describes beautiful native alternatives to specific invasive trees, shrubs, herbaceous plants, and grasses.

Native Trees, Shrubs, and Vines for Urban and Rural America: A Planting Design Manual for Environmental Designers by Gary L. Hightshoe

Looking for a mid-height native shrub, with great fall color, to plant in a shady site with acid soil? Or perhaps you need a small street tree that can withstand salt and soil compaction. This book can help you find a native plant for any site. A huge, expensive, but extremely useful reference work.

Bringing Nature Home: How You Can Sustain Wildlife with Native Plants, by Douglas Tallamy

The author, an entomologist, has a simple thesis: the more bugs you see, the healthier your backyard environment is. A strong argument for the use of native plants and sustainable gardening methods. The book that is turning people on to native plants today, as Stein’s books did 20 years ago.

Designing Gardens with Flora of the American East by Carolyn Summers

A fascinating new book by a landscape architect. Describes how to use native plants to create traditional gardens, even English cottage gardens and Japanese gardens. Good appendices listing many native plants, nurseries, street trees, etc.

Finally, I often recommend field guides to wildflowers, butterflies, trees, and shrubs as excellent resources for sustainable gardeners. I use the Peterson series, but you may find that you prefer a different one, such as Audubon. A particularly informative book is the Peterson Field Guide to Eastern Forests, which is an excellent reference on the ecology of forests. The Peterson Field Guide to Eastern Butterflies has extensive lists of host plants.

11/1/13: In the garden this week

Please excuse the bad photo–the wind was blowing and the little blue flowers I was focusing on sway in the slightest breeze. But aren’t those blue harebells (Campanula rotundifolia) lovely? they bloomed throughout June and July and are now reblooming with all their might (and as you can see, my favorite Rudbeckia, R. triloba) never stopped). The harebell is definitely on my list of plants to buy more of next spring. Notice the lovely red color on the Penstemon as well. Many native perennials turn brilliant colors in fall.

Now that the gardening season is just about over, take time to review the season, clean up the garden carefully, and continue to do routine chores like weeding. Here are the chores you might consider in the coming weeks:

– continue to harvest your fall vegetable garden: cool-weather crops such as lettuce, arugula, peas, and mustards (brassicas).

– keep the grass long (3″ or more) to reduce mowing times. Mow with a mulching mower and leave the clippings on the lawn, where they will serve as natural fertilizer. There is no need to water unless you are also reseeding (see below).

– early fall was the time to renew your lawn. If you fertilize your lawn (although this is not something I recommend), do it soon, before the lawn goes dormant, using a slow-release organic product. If patches have been reseeded, continue to water them until the temperature stays below 40 degrees.

— if you have places where grass won’t grow, consider planting something else next spring!

– as perennials finish blooming, leave the dead flowers on the plants. Collect seeds as they ripen; let most remain to feed the birds next winter. For most perennials, I will not remove any growth until early next spring.

– think about next year’s perennial garden: what needs to be cut back, moved, divided, replanted?

– allow winter squash to ripen after harvesting.

— we have had a killing frost, so remove dead plants: tender annual flowers such as marigolds and nasturtiums, eggplants, tomatoes, beans, cucumbers, tomatoes. Compost healthy plant material, discard plants that were attacked by insects or disease.

– take advantage of the relatively cool weather to do garden chores, such as fall cleanup, but do not prune now that woody plants are actively shedding their leaves. Now that we’re getting some rain, do some weeding.

— collect the leaves you need for the coming year’s compost pile

— many trees and shrubs can be planted in fall, but be sure to provide winter protection (mulch) and to keep watering until the ground freezes and again in spring if needed

Native plant walk on Sunday, Oct. 27

Please join me this Sunday, Oct. 27, at 1:00 p.m., at the Thielke Arboretum on Doremus Avenue in Glen Rock. I’ll be leading a walk through the woods to identify the many native plants found in this lovely example of a northern swamp forest. We’ll talk about the components of a forest, types of native forests, and the plants to be found in the arboretum in different seasons. The walk is short and easy for all. The rain date is Nov. 3.

This walk is sponsored by the Bergen-Passaic chapter of the Native Plant Society of New Jersey. For more information, contact the chapter at bergenpassaic@npsnj.org or the main group at npsnj.org.

9/27/13: In the garden this week

OK–I’m cheating. This photo was taken in the Thielke Arboretum here in Glen Rock, not in my garden. My site is much too dry for most ferns and for red maple.

The lovely cool weather continues, and rainfall amounts have been normal over the past month and year. I heard on NPR today that the season has been absolutely perfect for apples and that New York State will have its best apple harvest ever. So put apple picking and pie baking on your list of things to do this fall.

I am going on vacation soon, so this will be my last weekly update for a while. Here’s a list of tasks you might consider over the next few weeks:

– keep the grass long (3″ or more) to reduce mowing times. Mow with a mulching mower and leave the clippings on the lawn, where they will serve as natural fertilizer. There is no need to water unless you are also reseeding. Remember that the lawn will be in active growth as long as the temperature is above about 40 degress F.

– fall is the time to renew your lawn. If you fertilize your lawn (although this is not something I recommend), this is a good time to do it, using a slow-release organic product. If patches need reseeding, buy seed, sow it, and keep the newly sown patches damp. The weather is perfect. If you have places where grass won’t grow, consider planting something else there next spring!

– as perennials finish blooming, leave the dead flowers on the plants. Collect seeds as they ripen; let most remain to feed the birds during the winter. For most perennials, I will not remove any growth until early next spring.

– think about next year’s perennial garden: what needs to be cut back, moved, divided, replanted? The same goes for the vegetable garden: what did well or poorly? what pests or diseases appeared this season? what would you like to have more of?

– pick cool-weather crops such as greens and peas that you planted in late summer. Allow winter squash to ripen after harvesting.

— Pull up and discard (do not compost) warm-weather plants such as cucumbers, squash, beans, and tomatoes that are attacked by insects or disease. Start cleaning up the vegetable garden: remove warm-weather plants as they stop producing.

– Take advantage of the relatively cool weather to do garden chores: carry out remedial or cosmetic pruning as needed.

 

The Asteraceae (Part II)

This fall feels farther along than it really is because the  nights have been so cool. Trees are already showing considerable color. But many plants in the Asteraceae family are still hanging in there, showing their last few blossoms and continuing to ripen seeds.

Right now, it’s all about the asters: New England asters, several shade-loving species, sky-blue asters, heath asters (scads of tiny white flowers, not pictured). My garden is still full of color, and when the sun is out, the flowers still hum with pollinators.

Most of these will be in bloom for another month, barring very cold weather. Their seed won’t begin to ripen until frost, and plants in shady places are just showing buds.

Goldenrod (Solidago spp.) is aster’s invariable associate almost everywhere in the northeast. There are many, many species; the one in my garden is a volunteer; it’s about 3 feet tall, and it does well in both sun and part shade. Boltonia asteroides is another member of the tribe and also a good companion for the sun-loving asters. Boltonia began blooming even later than the asters–only about a week ago–and it too will bloom until frost.

Notice the Rudbeckia subtomentosa still blooming in the last picture. That species has many ripe seeds now even as it continues to bloom. Members of the Asteraceae family have now been blooming in my garden for well over three months, since the first Coreopsis opened in late May (I forgot about Coreopsis when I wrote my first post on the Asteraceae), and much longer, if you consider the early spring dandelions. Dandelions aside, consider planting some of these beautiful and carefree species–Asters, Rudbeckias, Echinaceas, goldenrod, liatris, ironweed, Boltonia–and their many cousins.

 

Watching grass grow

OK, this is not going to be an exciting post, at least not visually. We’re going to watch grass grow: I’m going to show you how to reseed small areas of lawn, since this is the perfect time of year and perfect weather to do it.

Reseeding a bare patch of lawn is easy if and only if you can keep the area damp while the grass is getting started. You’ll have to water gently a couple of times a day, more if the weather is hot. So here’s what you do:

Start by raking the area clear of all weeds and thatch, as I did on this small crescent-shaped area at the edge of my patio:

Next, scatter the seed rather thickly and as evenly as you can. Since I did this by hand, it’s not very even, but it will do. And buy the right grass seed for the area you’re reseeding. I bought a mix for high-traffic areas in full sun:

Finally, scatter a very thin layer (less than 1/4″) of compost, and water gently but thoroughly. I bought a small bag of organic compost for this task, because my compost is never free of weed seeds:

If you look closely, you’ll notice that you can still see some seed through the compost, and that’s OK–it’s better than a thick layer that would smother the germinating plants. Now the only thing left to do is to keep the area damp until the grass germinates, which takes about a week, depending on the weather.

Today, 9 days later, most of the grass is up (as is a dandelion I missed when I weeded):

If you look closely, you can see the new grass growing (it looks much better from the side). And that’s all there is to it–no fertilizer, no herbicides, no salt hay (although for a larger area that might be a good idea). Just seed and a little compost–and a gentle watering a couple of times a day.

 

9/20/13: In the garden this week

It’s not just trees that show fall color (although they are doing so remarkably early this year because of the very cool weather we’ve been enjoying). Many native perennials turn lovely colors in fall, like these sundrops in a bed on my front lawn. And notice the almost-ripe seed cluster of nodding pink onion (Allium cernuum) right behind the Rudbeckia flower at top left. It’s time to harvest seeds:

– last call to plant your fall vegetable garden: cool-weather crops such as lettuce, arugula, peas, and mustards (brassicas).

– keep the grass long (3″ or more) to reduce mowing times. Mow with a mulching mower and leave the clippings on the lawn, where they will serve as natural fertilizer. There is no need to water unless you are also reseeding (see below).

– fall is the time to renew your lawn. If you fertilize your lawn (although this is not something I recommend), this is a good time to do it, using a slow-release organic product. If patches need reseeding, buy seed, sow it, and keep the newly sown patches damp. The weather is perfect. If you have places where grass won’t grow, consider planting something else there next spring!

– as perennials finish blooming, leave the dead flowers on the plants. Collect seeds as they ripen; let most remain to feed the birds next winter. For most perennials, I will not remove any growth until early next spring.

– think about next year’s perennial garden: what needs to be cut back, moved, divided, replanted?

– harvest squash and beans before they get large and tough. Allow winter squash to ripen after harvesting. Pull up and discard (do not compost) warm-weather plants such as cucumbers, squash, and beans that are attacked by insects or disease.

– Because of the cool weather, tomato plants are pretty much done for the season. Consider harvesting the green tomatoes and pulling out the plants sooner rather than later to prevent the spread of the fungal diseases tomato plants are subject to

–Expect pest populations to decline naturally as the weather cools down.

– Take advantage of the relatively cool weather to do garden chores: carry out remedial or cosmetic pruning as needed, now that the ground is nice and wet, do some weeding.

We rarely get a spell of such beautiful early fall weather as we’ve had this week. The sun is warm, but the shadows are cool; we need a jacket to sit outdoors in late afternoon. Enjoy!