4/24/15: In the garden this week

A Christmas fern frond unfurls next to a columbine in one of my shade gardens. To the left an aster is emerging.

The weather is cold, which is really, really good for planting: plants grow roots when the soil is cool, and there’s much less danger of roots drying out. Any plant appropriate for our climate zone should do fine if planted now (just remember to water well). I am outdoors, with clients or in my own garden when I can snatch the time, all day this week and next.

Besides settling in new perennials, grasses, and shrubs, here are some other garden chores for the season:

— weed! This is the perfect time to rid your property of garlic mustard and to pull out tiny seedlings of annoying plants like English ivy and Norway maples (those are my particular annoyances; every property has some). Get them while they’re small.

— continue to direct sow seeds of early greens such as lettuce, spinach, arugula, mustard greens, and mesclun mix, plus peas and radishes. They’ll germinate and grow slowly at first, but with any luck you’ll have fresh salad greens in about 6 weeks. Sow a new crop every two weeks to ensure a continuous supply of spring greens until the weather heats up.

— If you started cold-season crops indoors, set them out in the garden now. Wait until late May to set out tender crops such as tomatoes, peppers, squash, and eggplant.

— clean up your perennial beds. Grab a handful of stalks hear the ground and gently bend them to break them off. Rake the detritus away and either compost it on site or, if you don’t have room for it, take it to your town’s compost center.

— evaluate the winter’s damage on your property. Don’t remove dead wood or broken branches unless they pose hazards to people or property, because they might be supplying food or shelter to winter-weary creatures, but see what needs doing. Do any areas need new mulch? Will your evergreens need spring pruning to remove winter damage? Do it as soon as new growth appears.

— it’s not too late to extend a garden bed or start a new one, and it’s always a great idea to eliminate some lawn: spread a 3-4 inch layer of cedar or hemlock bark mulch over the area now to kill the grass. You’ll be able to plant this season.

— monitor your garden for bird activity. Spring migrants are arriving and winter residents are very active at foraging and nest building. If you’re not seeing this, maybe your garden lacks winter food. There should still be perennial seeds, berries of less desirable plants, and leaf litter and dead wood for the birds to search for insects. If you’re not seeing birds, consider what you can do this season to attract them: for example, plant native perennials, stop pruning dead wood quite so aggressively, stop using pesticides.

— order your perennials and woody plants now to get the best selection. (Most local nurseries sell only a very few native species, so I rely on mail order and on specialty nurseries that are up to four hours away.)

— follow a sustainable lawn care regimen: wait until Memorial Day to fertilize. If you reseed bare areas, be sure to water often. Better still, if you have a place where grass won’t grow, plant something that will, like shade-loving native perennials.

— we got about three inches of badly needed rain this week, so no watering should be needed except for new plantings. Give all newly installed plants a good soaking as soon as you put them in the ground to settle them in and eliminate air pockets in the soil. Any week in which we receive less than an inch of rain, water all woody plants installed this spring or last season. Perennials planted last spring should be well-established, but those planted last fall and this spring will need supplemental watering during dry spells throughout this entire growing season. How do you know when we’ve received an inch of rain? I use a highly sophisticated rain gauge–an old yogurt container placed on the ground among the plants.

Cool weather is great for garden work, and it will make spring last longer! Enjoy it while it lasts.

The exquisite flowers of our lovely native plum, Prunus americana, are opening now.

We all make mistakes

Learn from my mistake: don’t plant an invasive because you think it’s pretty. or because you misidentify it as native.

About 15 years ago I admired pretty little plants with yellow flowers growing in a friend’s lawn, and with her permission, dug some up and planted them in my newly established mini-forest. I thought they were the native marsh marigold, Caltha palustris. My site is much drier than hers, so it took a few years for them to really take hold, but now they cover perhaps 20 square feet of my forest area, and the clumps expand every year. You’ve probably realized by now that I didn’t plant marsh marigolds. Instead, I mistakenly planted lesser celandine (Ranunculus ficaria), an invasive plant that’s extremely widespread in wet, shady areas throughout the Northeast.

Lesser celandine is almost impossible to dig up, because thousands of tiny bulblets are attached to the roots, the root system is very fine, and if you leave any bulblets the plants regrow vigorously. So this year I decided to try to smother it. As I clear my perennial beds, I’m dumping big piles of leaves on top of it. So far I’ve found that a six-inch layer of leaves isn’t enough: the plants grow right through. So I keep dumping more; probably at least some of it will die this year. And I’ll most likely weaken what remains. Right after the picture was taken, I buried the remaining clumps under about 18″ of leaf litter.

You may wonder why a plant like this is a problem. It’s pretty, it attracts pollinators, and it doesn’t strangle or otherwise hurt the native woody plants growing all around it. All true, but it crowds out natives. The forest floor used to be lovely with violets in spring and common lobelia in summer; now both are gone.

Some invasives can be difficult to distinguish from native plants. Look at this guide if you’re in doubt.

Happy Earth Day! We all make mistakes in the way we treat the earth, but we can all at least try to correct them.

Three square feet

If you have a sunny spot, you can have a beautiful, sustainable, environmentally friendly garden in just three square feet of space. How? Plant one milkweed,

Red or swamp milkweed, Asclepias incarnata, blooms in June and July, grows about 4 feet tall, and is not fussy about soil. Other choices include orange butterflyweed (A. tuberosa, shorter and fond of dry soil), or common milkweed (A. syriaca, pale pink flowers, not fussy about soil). Avoid tropical milkweed, A. curvassicava, which is not native.

one aster,

New England aster (Aster novae-angliae) begins blooming in August and doesn’t stop until hard frost. There are hundreds of Aster species for sunny sites. In addition to providing late season color, all are pollinator magnets and host plants for many species of native insects.

and one native grass.

Little bluestem (Schizachrium scoparium, 2-3 feet tall) is beautiful in all seasons and provides abundant seeds for birds in autumn. Grasses are host plants for the many species of butterflies in the skipper family. Little bluestem prefers poor soil; if your soil is richer, try prairie dropseed (Sporobolus heterolepsis, also 2-3 feet). Most native grasses bloom in late summer.

You will have flowers from late May through October, food for multitudes of insects, and host plants for many types of butterflies. And as an added bonus, deer and rabbits don’t eat milkweed or most native grasses.

4/17/15: In the garden this week

Serviceberry buds beginning to emerge. This picture was taken on the same day last year. the buds look just like this today.

Spring is finally here, and plants are emerging quickly and at at once. Forsythia, early magnolias, plums, and azaleas are finally in bloom. Ditto daffodils (all nonnative). I am looking every day for my Dutchman’s breeches and bloodroot. Ground-living bees are emerging. Birds are extremely active. Most perennials have poked their first shoots above the soil, so transplanting time is here. I am very, very busy.

Here are some things you might consider in your garden this week:

— continue to direct sow seeds of early greens such as lettuce, spinach, arugula, mustard greens, and mesclun mix, plus peas and radishes. They’ll germinate and grow slowly at first, but with any luck you’ll have fresh salad greens in about 6 weeks. Sow a new crop every two weeks to ensure a continuous supply of spring greens until the weather heats up.

— If you started cold-season crops indoors, set them out in the garden now. Wait until late May to set out tender crops such as tomatoes, peppers, squash, and eggplant.

— clean up your perennial beds. Grab a handful of stalks hear the ground and gently bend them to break them off. Rake the detritus away and either compost it on site or, if you don’t have room for it, take it to your town’s compost center.

— evaluate the winter’s damage on your property. Don’t remove dead wood or broken branches unless they pose hazards to people or property, because they might be supplying food or shelter to winter-weary creatures, but see what needs doing. Do any areas need new mulch? Will your evergreens need spring pruning to remove winter damage?

— it’s not too late to extend a garden bed or start a new one, and it’s always a great idea to eliminate some lawn: spread a 3-4 inch layer of cedar or hemlock bark mulch over the area now to kill the grass. You’ll be able to plant in late April or May.

— monitor your garden for bird activity. Spring migrants are arriving and winter residents are very active at foraging and nest building. If you’re not seeing this, maybe your garden lacks winter food. There should still be perennial seeds, berries of less desirable plants, and leaf litter and dead wood for the birds to search for insects. If you’re not seeing birds, consider what you can do this season to attract them: for example, plant native perennials, stop pruning dead wood quite so aggressively, stop using pesticides.

— order your perennials and woody plants now to get the best selection. (Most local nurseries sell only a very few native species, so I rely on mail order and on specialty nurseries that are up to four hours away.) If you wait until it’s time to plant, nurseries will be sold out of many species.

— follow a sustainable lawn care regimen: wait until Memorial Day to fertilize. If you reseed bare areas, be sure to water often. Better still, if you have a place where grass won’t grow, plant something that will, like shade-loving native perennials.

— last but not least, water last year’s plantings as needed. It’s been a dry spring so far; the soil is quite dry. Any week in which we receive less than an inch of rain, water all woody plants installed last season. Perennials planted last spring should be well-established, but those planted in the fall need supplemental watering during dry spells throughout this entire growing season. How do you know when we’ve received an inch of rain? I use a highly sophisticated rain gauge–an old yogurt container placed on the ground among the plants.

Buds of American plum, also taken on this same date last year.

Lovely

This violet is the first one to bloom for me this year, because of the extra heat it receives: it’s growing in a crack between the south-facing wall of our garage and a concrete walkway. Isn’t it lovely? And either an aster or penstemon seems to be growing out of the same crack–notice the oblong leaves in the center. Aren’t plants wonderful! All this and fritillaries, too!

Lying about lime

Do you apply lime to your lawn every year or have your lawn care company do it for you? If so, do you know why you’re applying it (and paying for it)? What does it do for your lawn? Here’s a hint: it won’t get rid of moss. I hear that misconception all the time.

Lime is a name for any number of chemicals used to raise the pH of the soil. pH, a measure of acidity or alkalinity, is expressed on a scale that runs from 0 (extremely acidic) to 14 (extremely alkaline). A pH of 7 is neutral, and most common garden plants prefer a soil pH of around 6.5, or slightly acid. If the soil is either too acidic or too alkaline, plants cannot use the essential nutrients in the soil. However, the soil in our region, in general, is slightly acidic—the pH is just fine.

So in most cases there’s no need to add lime. If you suspect that the pH of your soil needs correcting, the only way to find out for sure is with a soil test. And if you have been using nonorganic lawn care products for many years, your soil is much more likely to be too alkaline than too acidic. Hold off on the lime.

And what do you do if moss is growing instead of lawn? The presence of moss indicates a shady site, a site on which lawn grasses, which are adapted to sunny sites, will not grow. So you can get rid of the source of the shade, plant shade-loving plants instead of moss, or live with the moss, which is really quite beautiful.

A garden of moss: image from http://mountainmoss.com/learn-more/why-moss-2/

4/10/15: In the garden this week

Bloodroot (Sanguineum canadensis) in bloom in my garden in mid-April during a more favorable spring. Only about 6 inches tall, bloodroot is an important source of nectar for insects in early spring.

Do you remember when daffodils and forsythia used to bloom in mid-April and crab apples and lilacs bloomed reliably for Mother’s Day in mid-May? Perhaps I’m just showing my age, because when I was growing up, those were normal blooming times, whereas these days normal is about three weeks earlier. So you could think of this year as a normal, pre-climate change spring. Or you could just say, “I want it to be spring already!” like everyone else.

Today is dark and dreary, but less cold than it’s been, but the weekend is predicted to be warm and sunny. And once the weather warms up, the plants will react fast. So get out there this weekend and prepare your garden for spring:

— direct sow seeds of early greens such as lettuce, spinach, arugula, mustard greens, and mesclun mix, plus peas and radishes. They’ll germinate and grow slowly at first, but with any luck you’ll have fresh salad greens in about 6 weeks. Sow a new crop every two weeks to ensure a continuous supply of spring greens until the weather heats up.

— buy seeds of other vegetables and start them indoors according to this schedule so the seedlings will be ready for spring planting. If you started cold-season crops indoors, set them out in the garden now. Wait until late May to set out tender crops such as tomatoes, peppers, squash, and eggplant.

— clean up your perennial beds. Grab a handful of stalks hear the ground and gently bend them to break them off. Rake the detritus away and either compost it on site or, if you don’t have room for it, take it to your town’s compost center.

— evaluate the winter’s damage on your property. Don’t remove dead wood or broken branches unless they pose hazards to people or property, because they might be supplying food or shelter to winter-weary creatures, but see what needs doing. Do any areas need new mulch? Will your evergreens need spring pruning to remove winter damage?

— it’s not too late to extend a garden bed or start a new one, and it’s always a great idea to eliminate some lawn: spread a 3-4 inch layer of cedar or hemlock bark mulch over the area now to kill the grass. You’ll be able to plant in late April or May.

— monitor your garden for bird activity. Spring migrants are arriving and winter residents are very active at foraging and nest building. If you’re not seeing this, maybe your garden lacks winter food. There should still be perennial seeds, berries of less desirable plants, and leaf litter and dead wood for the birds to search for insects. If you’re not seeing birds, consider what you can do this season to attract them: for example, plant native perennials, stop pruning dead wood quite so aggressively, stop using pesticides.

— order your perennials and woody plants now to get the best selection. (Most local nurseries sell only a very few native species, so I rely on mail order and on specialty nurseries that are up to four hours away.) If you wait until it’s time to plant, nurseries will be sold out of many species.

— follow a sustainable lawn care regimen: wait until Memorial Day to fertilize. If you reseed bare areas, be sure to water often. Better still, if you have a place where grass won’t grow, plant something that will, like shade-loving native perennials.

— last but not least, water last year’s plantings as needed. Any week in which we receive less than an inch of rain, water all woody plants installed last season. Perennials planted last spring should be well-established, but those planted in the fall need supplemental watering during dry spells throughout this entire growing season. How do you know when we’ve received an inch of rain? I use a highly sophisticated rain gauge–an old yogurt container placed on the ground among the plants.

Enjoy the weekend! It really is spring!

The gorgeous flowers of serviceberry (Amelanchier spp.) will bloom in late April this year, about three weeks later than usual.

What’s up?

Very little–this spring is at least 3 weeks behind most recent years. And today is particularly cold, windy, dark and un-springlike. But it is nevertheless time to begin clearing away last year’s growth from the perennial beds, so for the past few days I’ve been working in my shade garden. The spring ephemerals that dominate this garden are the first to emerge, and if I wait too long to clear it, I risk smothering the new growth. Regular readers of this blog know that I advocate leaving the leaves that fall on the perennial beds to provide winter cover and insulation, and I practice what I preach. And in most gardens, I would not have to carefully remove the leaf layer at the first sign of new growth: plants can grow right through most leaf mulch. But my garden is surrounded by Norway maple trees, and their leaves form thick, impermeable layers. If I left them, the tender plants would not be able to get sunlight, and they would die. So I must remove the leaf mulch as well as last year’s growth of stalks that are still standing.

I’ve uncovered most of the shadiest bed, the one where the earliest wildflowers return year after year. The only new growth to be seen was leaf buds of wild ginger (Asarum canadensis); small basal rosettes of columbine (Aquilegia canadensis) and great blue lobelia (lobelia siphilitica); last year’s fern leaves, still nicely green; and tiny leaves of Virginia waterleaf (Hydrophyllum virginianum). I can’t believe I’ve never written about the latter plant before.

public domain image from Wikipedia

This is a great plant. It’s related to borage; it’s about 18 inches tall and works well as part of a shade garden or groundcover in the shade. It’s called “waterleaf” because the leaves look like they’ve been splashed with water. It blooms in May, and the flowers are most often lavender but may also be white. It spreads showly by means of rhizomes but never becomes aggressive, although it holds its own nicely against more aggressive spreaders like Canada anemone (Anemone canadensis).

Starting the vegetable garden; spring lawn care

No photos yet–my vegetable plot is just bare soil (dark and well-drained, enriched with homemade compost at least twice a year)–but yesterday I dug out some grass that was encroaching on my plot in the Glen Rock Community Garden and weeded a small area, and today I scattered seeds of a mesclun mix in that area. The gentle rain means I didn’t even have to water them in.

Speaking of seeds, I notice in my walks around towns that many lawn services have scattered lawn seed for their clients. It’s too early to seed a lawn, because the nights are still chilly, but if you are one of those clients, make sure you water the seeds at least twice a day until they have germinated and the new grass is at least an inch tall. Otherwise, you’re wasting both money and seed. Better yet, in future tell the lawn service not to seed unless they do it properly, preferably in early fall And make sure they use a seed mix that’s right for the specific site. Seeding a lawn is quite simple, but it does involve more than scattering seed.

Another thing that homeowners and lawn services like to scatter is lawn fertilizer or a combination product (fertilizer, pesticides, and herbicides). Again, it’s too early to fertilize, so you’re paying for something you don’t need. According to the most recent research on lawn care, lawns need no more than one feeding per year of slow-release organic fertilizer, not petroleum-based chemical fertilizer, and the best time to apply it is around Labor Day. Better yet, stop feeding altogether and rely on lawn clippings and fallen leaves to recycle nutrients back into the soil. The 4- or 5-step lawn care plan that many homeowners follow primarily benefits the chemical companies that manufacture the products and the lawn services that apply them.

What’s wonderful in early spring

Check out the website of the New York Botanical Garden for a confirmation of my hunch that this growing season will be both late (about 3 weeks late, by the Garden’s estimate) and spectacular. And then make time to get to the Garden this spring to enjoy the early flowering bulbs (right now), magnolias, daffodils, and flowering cherries. Not to mention the new native plant garden.

Photo from http://www.nybg.org/gardens/plants/magnolias.php, the New York Botanical Garden