A paradigm shift

To switch my garden paradigm to one that’s more wildlife-friendly, I find that I need to keep catching myself when I fall into familiar routines. One of these is the fall garden clean-up. 

Looks messy, doesn't it?

    Conventional garden wisdom advises pulling out annuals and cutting back perennials in fall to prevent unwanted insects from over-wintering on their leftover stalks. My goal used to be to leave the garden beds clear of above-ground herbaceous plant manifestations during the winter. This was when evergreen shrubs and trees were supposed to carry the aesthetic burden.

Evergreens are supposed to provide winter interest

    This year I planted my insectary garden, intending to attract native insects. In October, without thinking about it, I almost followed my usual practice, which had been to cut the plants to the ground after the first hard frost and then blanket the soil for the winter in a thick layer of compost. Luckily I realized this habit wouldn’t fit the new paradigm.
    Providing shelter for over-wintering insects is part of what I’m trying to do now. This year I’m going to leave the annuals and perennials standing through the winter. I spread compost around them, and I’ll cut them down in spring when new growth is about to start.

Insectary garden under the new plan. Parsley is still green.

    This should help birds as well as insects. Check out Gardening for the Birds: How to Create a Bird-Friendly Backyard, a fascinating book by George Adams. He proposes making gardens that offer food, shelter and nesting sites for native birds. That includes attracting insects for birds to eat. It also means leaving flowers alone when they go to seed, because many provide useful food for birds.
    Following Adams’ directions, I’m leaving seed stalks standing on perennial oxe-eye daisies, asters, goldenrod, and coneflowers, and annual sunflowers, cosmos, snapdragons, zinnias, and black-eyed Susans.
    A lot of these plants have similar-shaped daisy flowers because they are from the same taxonomic family, the Asteraceae. In this group of plants what looks like a single daisy is actually a composite of many smaller flowers. The petals are ray flowers, and the central disc is made up of tiny disc flowers.

Black-eyed Susans gone to seed

Apparently this makes for good foraging for both insects and birds. I’ll be watching to see if I can observe birds feeding on the flower heads during the winter.

Leaf mulch--manna from heaven

This week most of the maples on our street dropped their leaves, and the oaks' leaves are starting to fall. This is the last burst of glory before the bare gray and brown landscape of winter sets in. It’s time to make leaf mulch.

Last leaves

            When we bought our house thirty years ago and moved to the suburbs, I imagined that I would let fallen leaves lie on my beds through the winter as mulch. This worked around the fence line, but in more open areas, the leaves wouldn’t stay put. I quickly sensed that neighbors were not happy when leaves blew over from our property to theirs. Local custom demands that yards be absolutely leaf-free going into winter. 

            The reason to use leaves for mulch was not just to divert them from the waste stream. I wanted to keep falling leaves on our property so that nutrients the trees pulled from the air and soil to make foliage could stay here and be recycled. I know that some people have luck grinding up leaves by running a lawnmower over them. This never worked for me, and anyway, I wanted to spend as little time as possible behind the gas-powered machine we used at the time. So I invested in a leaf shredder.

            This electric tool is essentially a string trimmer in a drum. Whirling plastic filaments chop the leaves, and they drop down into a barrel, a bag, or directly onto the soil where they’re wanted. To use the leaf shredder takes some effort, plus goggles, a mask, and wrist-covering leather gloves. It’s loud, and it makes a lot of dust. The plastic filaments wear down and have to be replaced frequently. Sticks clog the drum, so they have to be picked out of the leaves as I feed them in. Leaves that are wet, or even damp, are much slower to process.

            Yet despite the drawbacks, hours spent feeding leaves into the drum prove well worthwhile. The chopped leaves make pleasant, fluffy brown mulch that looks neat and stays where I put it.

Conventional garden wisdom warns against piling mulch against a tree's trunk lest voles or other small animals chew through the bark in winter. That's never happened in my yard.

The leaf mulch lasts for at least a year and improves soil quality by contributing organic matter as it decomposes.

Last year's mulch, almost fully decomposed

            Now I’m in the strange position of not having enough tree leaves. I need more to make the amount of mulch I want. I ask neighbors if I can carry away some of their leaves. They humor me, but they sometimes give me quizzical looks. They don’t know that they’re giving away the garden equivalent of manna from heaven.  

An insect's autumn buffet

This spring I set a goal to have something blooming all season to attract and feed native insects.

            Despite my efforts over the years to plant for flowers throughout the growing season, my garden still has the most flowers in spring and early summer. Flowering trees and shrubs put on their show from late April through June. 

Mid May--a great time in the garden

            The majority of my perennials also bloom in spring. In July I’m down to lilies and daylilies. By August there’s a decided lull

Mid-August doldrums

            This spring I planted a small bed specifically for the benefit of insects (see Bugs welcome), aiming to have flowers available until the end of the garden season, which is coming up soon now. The black-eyed Susans (Rudbeckia hirta) and sweet alyssum (Lobularia maritima) I planted bloomed steadily through the summer. 

Black-eyed Susan flowers are fading, 
leaving seeds for birds.

Sweet alyssum is still going strong

In September, as the summer bloomers went to seed, New England asters (Symphyotrichum novae-angliae) picked up the baton.

A New England aster blooming happily in October

            It’s easy to forget what a great time fall is for flowers. On September 26, 2013 I counted twenty-seven different kinds of plants in bloom in beds and containers. Even now on November 1 there are a few flowers on the last of the fall and summer bloomers, 

Stonecrop (Sedum 'Rosy Glow')

and some spring bloomers are back with a last round of blossoms before the snow sets in. 

Roses that quit in the summer often bloom again
 until surprisingly late fall

            Cold and drought—we’ve had both in the past month—can signal plants to put energy into making flowers and seeds before they die or go dormant for the winter. They sacrifice some of their stored energy toward the goal of passing on their genes. Summer heat puts some plants into a state of dormancy (that would certainly apply to my pathetic lawn grass) in which non-essential functions like making flowers and new leaves are put on hold to save energy. In fall these plants come back to active growth and some resume flowering.

            Other plants take their cue from the length of the nights. Their pattern of flowering in spring and fall is mediated by the balance between two forms of the pigment phytochrome (If you want to know more about this and other nuggets of plant physiology useful to gardeners, I highly recommend How Plants Work, a new book by Linda Chalker-Scott, who blogs at gardenprofessors.com).

            The reason the black-eyed Susans start flowering in June is that they are “long day” (short night) plants, triggered to bloom by shorter summer nights. Dahlias wait until later to make flowers because their signal is the longer nights of late summer and fall.

            Next year I hope to expand my offerings of nectar and pollen at the end of the summer to make sure that insects can find what they need in my yard. It’s all part of a new understanding—we need the insects at the base of the food web so that all the animals, including humans,can eat.