Flower cluster of grey dogwood (Cornus racemosa), the loveliest dogwood of all. This plant will bloom within the next week or 10 days.
These next couple of weeks are the loveliest of the year in the garden, and we will miss it all—we are going on vacation. So I thought that in this post I would look ahead a bit and tell you what to expect in the next two or three weeks. In that time, the garden will switch from spring to summer.
It's delightful that the drought of the past two years seems to have lifted. Rainfall is slightly above average for the past 30 days and normal for the year to date. As a result, we are enjoying a truly lovely spring. And the relatively cool temperatures mean that all the beauty around is lasts a bit longer than it would if the weather suddenly turned hot. It gives us all a longer spring planting season as well. I like to stop planting when the weather really warms up.
— water new plantings if the weather turns dry: Rainfall totals are finally normal or even a bit above, at least in the short term. We've received approximately an inch and a half of rain this weekend, so no need to water. But always water well after planting to settle the new plants in the ground, and check back here weekly for updates: In any week in which we receive less than an inch of rain, water all plants installed this spring or last fall. How do you know when we've received an inch of rain? You can make a highly sophisticated rain gauge–an old plastic container or tin can placed among the plants. I total the weekly rainfall and decide whether to water my new trees or my clients' new plantings each week.
—plant trees and other woody plants. Don't wait too long—the earlier you plant, the more time trees and shrubs will have to establish before the weather really heats up. Same goes for perennials and grasses. The earlier the better. If you must keep planting once the weather really turns hot, be sure to water copiously.
—provide prophylactic care for trees. Several native tree species are at great risk of succumbing to invasive insect infestations. Hemlocks should be sprayed with dormant oil (which is not a pesticide) in early spring and early fall. Ash trees should be treated for emerald ash borer. The best time is while they are leafing out, so it's a bit late. Consult a qualified arborist if you're not sure if you have hemlocks or ashes; he or she can then recommend the best treatment options.
— continue to start vegetable seeds indoors. You'll find a schedule here. Get the vegetable garden ready for the coming season by weeding, raking the soil smooth, and adding compost or well-rotted manure. Compost can simply be spread on top of the soil; manure should be mixed in, and make sure it's not fresh manure. Once the soil is prepared, you can plant seeds of cool-weather crops such as mesclun, spinach, arugula, peas, and beets in the garden. Do not set out warm weather crops like tomatoes, squash, basil, and eggplant until the last week in May. Right now the nights are still too cool, and the plants will not grow properly.
— After cleaning up the perennial garden, continue to plant perennials and to divide and move them as they emerge. The earlier you divide or move perennials and grasses, the quicker they will establish. Even finicky, hard-to-divide plants will respond well. And it's much easier to divide and replant a few plants at a time than to dig up an entire bed. IF the weather turns hot, either stop planting or increase the amount of water you provide.
— the cool weather is a great time to reseed bare patches of lawn, but be sure to keep the seeded areas moist until the seed sprouts. It's too early to feed your lawn, no matter what your lawn-care service tells you. Wait until Memorial Day, and then use a slow-release organic fertilizer. Or best of all, don't feed at all this year. The lawn will look just fine. Avoid pesticides, fungicides, and herbicides. Remember that pesticides kill butterfly and firefly larvae and native ground-dwelling bees as well as "bad" insects. And garden chemicals are not so great for kids or pets either; common herbicides, in addition to killing butterfly host plants like violets, are carcinogens. Best to avoid them.
— Support a local farmer by joining a CSA (community supported agriculture) this season. CSAs allow you to support small-scale, sustainable agriculture and help limit the environmental effects of factory farming. You'll also find that the produce tastes much, much better than what you buy in the supermarket. For the past 5 years or more, we have joined Hesperides Organica, a family-run farm located in Hawthorne, NY. They deliver weekly to various locations in Bergen County.
I hope you're enjoying this lovely, slow-to-emerge spring as much as I am. It's very hard to tear myself away from the garden.
Canada anemone, Anemone canadensis, is a lovely ground cover, but it can be a bit of a thug in the garden. Be sure to plant it where you can contain it.
Chokeberry (this is black chokeberry, Aronia melanocarpa) is in full bloom now. In August, it will produce large black berries for birds (and jam); in fall, the foliage will be brilliant orange and red.
Planting season is in full swing, and I am grateful for this very rainy day. The ground was getting too dry to plant without watering first, and I'm in the middle of a very busy planting season. I like to finish planting perennials, grasses, and shrubs before Memorial Day, although you can plant later if you can water frequently. Roots grow best when the soil is cool.
You're probably thinking about preparing your yard for outdoor living: setting up the patio and grill, uncovering the pool, planting ornamentals. Give some thought to sustainability as well as to livability. Consider planting native perennials instead of annuals (less watering, less work every spring); using fewer chemicals on the lawn (less expensive, kinder to the environment); welcoming pollinators and birds (planting natives, avoiding pesticides). Maybe there are some areas of lawn that could be replanted as flowers or vegetables. Maybe you can water less often this season.
— water new plantings: Rainfall totals are finally normal or even a bit above, at least in the short term. We've received approximately an inch and a half of rain today so far, so no need to water. But always water well after planting to settle the new plants in the ground, and check back here weekly for updates: In any week in which we receive less than an inch of rain, water all plants installed this spring or last fall. How do you know when we've received an inch of rain? You can make a highly sophisticated rain gauge–an old plastic container or tin can placed among the plants. I total the weekly rainfall and decide whether to water my new trees or my clients' new plantings each week.
—plant trees and other woody plants. Don't wait too long—the earlier you plant, the more time trees and shrubs will have to establish before the weather really heats up. Same goes for perennials and grasses. The earlier the better.
—provide prophylactic care for trees. Several native tree species are at great risk of succumbing to invasive insect infestations. Hemlocks should be sprayed with dormant oil (which is not a pesticide) in early spring and early fall. Ash trees should be treated for emerald ash borer. Consult a qualified arborist if you're not sure if you have hemlocks or ashes; he or she can then recommend the best treatment options.
— continue to start vegetable seeds indoors. You'll find a schedule here. Get the vegetable garden ready for the coming season by weeding, raking the soil smooth, and adding compost or well-rotted manure. Compost can simply be spread on top of the soil; manure should be mixed in, and make sure it's not fresh manure. Once the soil is prepared, you can plant seeds of cool-weather crops such as mesclun, spinach, arugula, peas, and beets in the garden. Do not set out warm weather crops like tomatoes and eggplant for another few weeks.
— After cleaning up the perennial garden, continue to plant perennials and to divide and move them as they emerge. The earlier you divide or move perennials and grasses, the quicker they will establish. Even finicky, hard-to-divide plants will respond well. And it's much easier to divide and replant a few plants at a time than to dig up an entire bed.
— it's much too early to feed your lawn, no matter what your lawn-care service tells you. Wait until Memorial Day, and then use a slow-release organic fertilizer. Or best of all, don't feed at all this year. The lawn will look just fine. Remember that pesticides kill butterfly and firefly larvae and native ground-dwelling bees as well as "bad" insects. And garden chemicals are not so great for kids or pets either; common herbicides are carcinogens. Best to avoid them.
Enjoy the garden this week.
Lovely foamflower (Tiarella cordifolia) is in full bloom now in my garden.
Who knew that columbine has a species-specific butterfly? I didn't until I noticed a few skeletonized leaveson a couple of plants–chewed leaves with nothing left but the ribs. Normally columbine leaves do not get chewed, and the plant's only pest is leaf miners, which don't appear until summer. Looking closely at the leaves, I saw a few more with damage only at the leaf margins, a sign that caterpillars were at work rather than, say, beetles.
Caterpillars of columbine duskywing, Erynnis lucilius, on native columbine.
I turned to my trusty Peterson's Field Guide to Eastern Butterflies, which has an index to host plants as well as to butterfly species–an extremely useful feature. I looked up columbine and found that there is a species-specific butterfly, that its caterpillar is green with some yellow features, and that the season is correct. Bulls eye. I also found more about the species's life cycle on the Butterflies and Moths of North American website.
For those of you who worry about insect damage to your plants, be aware that this small plant is in bloom while the chewing is going on. So if you want to see butterflies, hold off on the pesticides and be willing to tolerate a few chewed leaves.
Also, remember that ecological gardening takes time. I've been growing columbine for over 20 years, and I've never seen this caterpillar before. According to the references, this butterfly inhabits woodlands and rocky slopes (where columbine lives in the wild), not suburbs. So how did the mother butterfly find my columbine plants last fall? And think what would have happened if I did a rigorous garden cleanup in fall–the overwintering eggs probably would have been destroyed. Think about all the things that must go right for a few tiny caterpillars to survive.
Once again, this story shows that if you plant it, they will come. It's always amazing.