May is the month when everything seems possible in the garden: The vegetation is lush and unblemished, and the steady warmth draws out the clematis, chive blossoms and the first of the roses.
The whole merry scene is enlivened by songbirds. Residents such as cardinals, goldfinches and chickadees were joined weeks ago by the robins and, more recently, by such feathered treasures as yellow-rumped warblers and a pair of catbirds that call my garden their summer home year after year. This is just a partial list; I could add juncos, wrens, white-throated sparrows, doves and various raptors, including an osprey.
You can draw wildlife with specific plantings, but I have found that a garden cultivated for its diversity and long season of interest will also appeal to birds and other animals. I have a fish pond, shrubs and evergreens that provide shelter to roost, and plants rich in nectar and berries.
I don’t use pesticides (apart from Bt on the cabbages), and I work organically in a way that provides for a rich array of creatures that live in the soil or on the wing. This provides poison-free food for the birds.
Encouraging the birds’ arrival is just the half of it, because their appearance coincides with that time of year when they are driven to construct nests, lay eggs and raise their young.
Entomologist Doug Tallamy, author of “Bringing Nature Home,” says birds and other wildlife have come to rely on native plants that foster a rich insect life. Caterpillars, he says, are the best food for new birds. I attended an event recently where he made a compelling case for planting trees such as red oaks, which foster scores of insect species. “Caterpillars are excellent baby food,” he told a gathering at the New York Botanical Garden. “They’re soft, they’re high in protein and easy to digest.”
A single pair of chickadees will bring its young between 390 and 570 caterpillars a day, working from 6 a.m. to 8 p.m., he said. Before the chicks fledge, they will have eaten as many as 9,000 little caterpillars. As frenetic and exhausting as it is for the birds, it’s pretty draining for the bird-watcher as well.
In the back of the house, I have a downspout that rises about 15 feet before moving out to a projecting eave. At the fork between pipe and house wall, a robin built a nest and set about raising a family. The mother cannot alight directly onto the nest: She arrives by bouncing between wall and drainpipe in a way that strikes a note. The nest is not hidden, but it’s virtually impossible for predators to reach.
Mr. and Mrs. Cardinal have adopted a different approach. They built their nest in the thorny veil of a rambling rose whose buds are growing noticeably by the day, as are the chicks in the nest. The rose and its nest adjoin a screened porch. At about four feet above the ground, the nest is clearly seen from the porch. When the mother leaves, there is a heartwarming show of young, vulnerable life.
The cabaret began with the nest building before, lo, the appearance of four eggs, light in color with tan specks.
Some of the things you learn about cardinals at close quarters: The female can chirp with her mouth full; and she and her mate can talk to each other across a crowded garden. The chicks emerge as little quivering blobs, but their rate of growth is astonishing. Within a week they fill the whole nest, peep to their mother and generally sleep in a big huddled mass of fluff that can erupt into a gape-beaked feeding frenzy, even when the meal is phantom. I have seen the female and male feeding their young at the same time.
Two weeks after hatching, the babies are ready to venture out of the nest. This is tough on everyone concerned. The price of forming an attachment to these beautiful creatures can be grief, for even with everything working in their favor, many hatchlings won’t survive.
“There’s a learning period, and not all young birds make it through the learning period,” said Stephanie Mason, senior naturalist at the Audubon Naturalist Society in Chevy Chase.
Just graduating to fledgling is an achievement. Jason Martin, who leads a project at the Cornell Lab of Ornithology called NestWatch, said that all manner of predators eat eggs and hatchlings. The list, surprisingly, includes squirrels, chipmunks and even deer.
Once out of the nest, the fledglings are weak fliers and too trusting, and can fall victim to large birds such as crows and, significantly, to cats.
The location of the nest can create an uneasy situation between us and them, especially if it’s close to a door or much-used patio, deck or, yes, porch.
“A lot of birds that do nest in back yards are somewhat tolerant of human beings,” Martin said. “Cardinals and robins are used to people being around, though any bird can get disturbed if you get too close to the nest.”
Under the program he runs, citizen scientists are encouraged to study nesting, but sensitively: Participants are advised to visit a nest every three to four days (when the parent bird is away) and spend less than a minute gathering data on eggs and hatchlings. The Cornell Lab has been using the results since the 1960s to assess changing patterns in the range and nesting seasons of various species.
If you need to trim hedges and shrubbery, it is better to tackle the task a month from now, after the main nesting season and after the hedge is done with its annual flush of growth.
If you are reworking a part of the garden, don’t rip out shrubs or relieve them of vines until you are sure there are no nesting birds. And keep your cat inside or under close supervision during fledgling time. Dogs too can kill helpless birds.
What should you do if you see a fledgling in the garden? Leave it alone; a parent bird is probably nearby and will return when you leave. Don’t put it back in the nest, and don’t try to feed it.
“You can have a baby bird out of the nest before it’s ready — downy and can’t fly,” said Martin. “In that case if the nest is nearby and still active you can try to gently pick it up and place it back again. But if that baby bird has feathers, with eyes wide open, it’s probably going to be fine.”
The gardener, on the other hand, will be a nervous wreck.
Read past columns by Higgins at washingtonpost.com/home.
@adrian_higgins on Twitter