Inconvenient clover

Speaking this week to the Wellfleet Gardeners, a wonderful group of serious gardeners on Cape Cod, reminded me of one of my favorite stories about how commercial influences form our ideas about the plants around us. Wellfleet readers, I apologize for repeating what you just heard. Tune in next week when I should be able to describe the beginning of the sheet composting experiment.

     After World War II, Americans embraced what a team of environmental scientists at Yale has termed the Industrial Lawn, defined as closely mowed, continuously green, and ideally free of weeds and pests. The Industrial Lawn requires regular inputs of water, fertilizer, pesticides, and herbicides. Energy costs are high, not just for mowing but also for synthesizing and transporting the chemicals used.

Industrial Lawn: turf grass only

     Why did we Americans embrace this Industrial Lawn, and why right after World War II? One reason was the development of an herbicide, 2,4-D, for use by the military (If this name sounds familiar, it might be because of Agent Orange, which contained both 2,4-D and 2,4,5-T, another phenoxy herbicide). During the war, chemists in England and the US raced to develop an herbicide that could wipe out German potato crops and Japanese rice, to starve out the enemy.

Spraying herbicide over Vietnam

     To their disappointment, potato and rice plants turned out to be resistant to 2,4-D. It did kill broadleaf plants in turf, though, without killing the grass. The Scotts company realized this could be a goldmine. In 1947, Scotts started selling 2,4-D in their Weed and Feed combination—herbicide plus fertilizer. Scotts had just one problem. Their new weedkiller killed clover.

     Before the war, grass seed mixes included clover seed. White or Dutch clover originated in southeastern Europe and Asia minor. It’s spread all over the world because it works so well for pastures—and lawns. I like to use clover to fill in bare patches in my lawn. Rabbits love it, and I think it’s keeping them from wiping out my perennials.

Rabbits like clover-photo ibm4381

     Clover is a legume that fixes nitrogen in the soil, in effect making lawn fertilizer. It stays green all summer; it’s easy to grow, drought tolerant, and pest free. It aerates the soil. It stays low. Dog urine doesn’t cause it to discolor; and it attracts bees and beneficial wasps that control leaf-eating insects. It sounds like an asset for any lawn, right? Before the war, that’s how it was marketed.

To me, clover looks good in a lawn

     But because of 2,4-D, Scotts changed their marketing approach. They told consumers that clover was a weed. That idea persists up to the present time; lawn care contractors still cringe at the sight of clover in the lawn.

Making killing clover a selling point

     Although we like to think that advertising doesn’t affect us, this kind of messaging has an impact. Don’t be fooled. I’m trying to grow less lawn and convert the space to more environmentally friendly uses. No matter how much lawn you like to maintain, though, don’t let anyone convince you that clover shouldn’t be part of it.

A safe place

While I’m trying to prioritize native plants, I still enjoy lots of the nonnatives I chose over the years. My climbing hydrangea (Hydrangea anomala subsp. petiolaris) is one of those imports. Garden designer Betsy Brown recommended this Asian plant back in the 1990s, and it hasn’t disappointed.

Climbing hydrangea flowering in June

After a slow start, it now covers itself every June with romantic clouds of white “lacecap” flowers, which I prefer to the “mophead” puffball blooms of some hydrangea shrubs. It clings to the bark of a towering oak next to the corner of the garage with sticktight adhesive pads, no supports needed. 

 

The vine attaches to the oak's bark

 
Every time I sit at the kitchen table or stand at the sink, I can check out what’s going on with this vine. And there’s a lot happening.

    This winter I particularly notice what great shelter this vine provides for birds. Chickadees in particular seem to find it a great perch, and flocks of dark-eyed juncos frequent it too. 

Black-capped chickadees perch in the shelter of lateral twigs

They benefit from the vine’s growth habit. It sends out horizontal shoots from the main stems that hold leaves and flowers during the growing season. There are so many of these side shoots that they create a protected area along the trunk where birds seem to feel safe. Squirrels find the combination of the tree and the vine a very reassuring place. 

Squirrels take advantage of the vine's shelter

A British blogger observes pollinators including bees and hoverflies on a climbing hydrangea he grows in an aluminum trash bin on his balcony, so insects benefit too.

    With the leaves down, the vine’s main protection for creatures that are active in winter comes from the nimbus of twigs. In summer, as you can imagine, it’s a much better hiding place. The hydrangea's shiny bright green heart-shaped leaves afford privacy for squirrels as they dash up and down the trunk on their way to a Norway spruce that hangs over the garage. 

Lattice and vine together provide safety

A major section of the vine has attached to the lattice on the garage wall that I put up to support clematis vines. At the top of the lattice panels, birds have enough space to perch and socialize. A cardinal couple built their nest nearby in the heart of an evergreen shrub.

    A few weeks ago during a warm spell, I found the grisly remains of a squirrel, just the head and tail. Hawks have joined the backyard ecosystem. That must be why the climbing hydrangea is such as welcome sheltering perch for smaller birds.

Cooper's hawks prey on backyard birds and squirrels

    This spring I plan to create another bird shelter in the yard, a brush pile. In an open garden, this could look too messy, but fortunately I have space among evergreen trees where I can pile up fallen branches loosely without creating an eyesore. This will be an extra place where birds can hide out when it’s cold or predators are around. I can place it near a bird feeder and a water source to make it attractive. It won’t provide the great show I get from that hydrangea vine, though.

Native honeysuckle offers wildlife benefits too

Abetting the soil cycle

I’ve learned something new from ecological garden designer Larry Weaner: soil can be too rich. In Garden Revolution, Weaner describes telling contractors that he doesn’t want to add topsoil, compost or fertilizer before he plants a meadow. They think he’s crazy to turn down traditional first steps for establishing a new landscape. His point is that the plants he’s going to be growing can outcompete weeds in lean soil but not in soil that’s full of nutrients and organic matter. Those will only jump-start invasive weeds.

Northeastern meadow plants such as goldenrod thrive on lean, dry soil

    Weaner and other ecological gardeners aim to restore and imitate natural processes. When he plants a native meadow, he works with the soil that’s present and the plants that are adapted to grow on it. How does this principle apply in my garden setting, which becomes more like a woodland every year as the trees grow taller?

The yard is starting to resemble a clearing in a forest

    Last fall I doubled down on my strategy of letting fall leaves lie on the garden through the winter. Some of those will be raked off to mix with wood chips in the sheet composting experiment. The rest will stay where they are under trees and shrubs. 

    Bagging up and sending away those fall leaves would deplete my own soil, because what the trees drew from the soil to make leaves wouldn’t be replenished through decomposition. Trees have their own recycling operation going, if we just stay out of the way. I want those leaves on the ground, and not just to provide shelter for native insects in various stages of development. They’re also there to build soil that will nourish plants and sequester carbon.

Leaves on the ground serve important purposes

     But is it possible that the leaves and the compost I spread around will make my sandy soil too rich? Not for the woodland plants I want to grow. 

     A neighbor told us that our yard was once part of a gravel quarry. That’s easy to believe when I dig through a thin layer of topsoil and hit sand and gravel. If this were an unsettled area, it would probably be an oak-hickory woodland, the most common plant community for the region. The ground would be covered with forest duff—fallen leaves and twigs that would gradually break down and become part of the soil.

What the yard would look like without human intervention?

    In my garden I want to foster this soil cycle that converts leaves to humus and back to leaves again. The natural system will maintain the right nutrient balance.

    Over the years I’ve focused hard on making compost, and I still love the idea that you can turn garden waste into something great for your soil and plants. But by moving dead plants and fall leaves to the compost piles, I’ve been taking them away from where they’d otherwise decompose in place. Then I have to load compost into the wheelbarrow to replace organic material in the spots I removed it from. That’s starting to seem foolish.

Why carry compost ingredients to the pile and back?

    By letting the leaves compost where they fall, I hope to imitate the natural process more closely—and save work, too.

Witch hazel is blooming. Can spring be far off?

I'll be away for two weeks. See you the week of March 18.