Targeting Invasive Plants

My latest article, Plant Pests, is featured in the Green Thumb Guide of the Spring 2009 issue of Nature’s Garden, one of the most popular Better Homes and Gardens gardening magazines, on newsstands now. The Nature’s Garden website http://bhgnaturesgarden.com/ offers a place to share your nature photos, to keep a journal, or to participate in garden forums. Take a few minutes now to check it out.

For those of us in the conservation trenches, it’s a watershed moment when magazine editors acknowledge that some plants that are still being sold in garden centers across the nation are actually thugs that can drive out native vegetation and destroy habitat. Let’s support those who do.

But many invasive plants have been here so long that people mistake them for natives. One of the earliest harbingers of spring (just 50 days away) in our area is the invasive Garlic Mustard (Photo credit: Olivia Kwon). Like many plants that have taken over our woodlands, Garlic Mustard arrived in America with the European colonists, who innocently planted it in their herb gardens. Now found all across the Northeast, the South, and parts of the Midwest, Garlic Mustard is spread by tiny seeds that are produced by the thousands on a single plant. The seeds are spread by birds, as well as forest and domestic mammals. They can stick to shoes, socks, and pantlegs, so that people hiking through the woods may, unintentionally, carry them far and wide.

Garlic Mustard exudes a chemical that kills off the competition by preventing the germination of native plant and wildflower seeds. Its own seeds can survive on the forest floor for five to ten years. But the situation isn’t hopeless.

In our woods, we never had a problem with Garlic Mustard, until the deer ate all of the Virginia Creeper. Apparently the large leaves of that plant provided sufficient shade to inhibit Garlic Mustard seeds from sprouting. Local land stewards advised us to weedwhack our acres of mustard every year, so that we would eventually be cutting only first-year plants (Garlic Mustard is a biennial that sets seed in the second year). This is a long-term approach, with the goal of eventually exhausting the seed bank. And, so far, it’s been working. We have also managed to keep the mustard from crossing a mulch path that separates it from an area of the woods where native violets and White Snakeroot abound.

In the garden itself, we pull the plants by hand, an inexplicably satisfying experience. This is best done after a rain, when the roots come out of the ground with little effort. If seed has already set, even if the seed pods are green, DO NOT put Garlic Mustard on the compost pile.

To watch a video designed to help identify and control this pest, click

http://www.vimeo.com/2855779

Gardening as Process: Zeroing-in

At this point, you should have a bubble diagram that shows: Your planned activity areas, both hardscape and plantscape; an inventory of what will be left once you’ve moved, or removed, what you don’t like; and a rough indication of where you want various types of new features and plants --- trees, shrubs, perennials, and annuals.

For some, the next step is the most difficult: Choosing how you want your garden to grow. Do you want to look out on masses of a specific color? Do you want to collect a variety of the same species of plants, such as roses, or hostas? Do you want to create a particular kind of garden, such as an alpine garden, a Japanese garden, a vegetable garden, or a cutting garden? Do you want the garden to have a casual look, like a swath of rough grass and meadow? Or do you favor a formal look with edged beds or parterres framed with boxwood?

Each of these choices calls for a different selection of plants. Once you’ve made these decisions, it’s time to break out the reference books and plant catalogs to create a list of what to buy and how much it all will cost. This is your wish list.

Next, add up the cost of everything on your wish list. Even if you can afford everything on the list, think about how much time and effort it will take to install it all. Can you get it done in one growing season? If the cost is too far beyond your budget, or the work can’t all be done in one season, consider breaking your plan into more manageable phases. If you choose this route, plan to install any paths, rock walls, structures, or other permanent features first. Construction is messy work and your plants won’t survive the disruption.

Don’t buy anything that’s not on your list. After a winter spent looking at leafless branches, it’s easy to be tempted by every colorful flower in the nursery and, before you know it, your garden will look nothing like your original vision.

Stay focused and follow your plan; it’s the map to the garden of your dreams.

Gardening as Process: Editing

Over time, we change, our taste changes, the availability of various plants changes, the amount of time we want to spend in the garden changes and, most telling, our capabilities to manage the physical tasks of gardening changes. What this means to every gardener is that the garden should be periodically edited.

When? When it no longer functions as intended, when the flower beds have grown too shady, when the kids no longer use the sandbox or swing set, when the swimming pool lies idle 99% of the time, when the garden no longer gives you the pleasure it once did. And, sadly, when we can no longer maintain what we have.

Edit your garden to suit your lifestyle and your budget. As with everything in life, gardening happiness is directly proportional to the difference between our expectations and our ability to achieve them. If you can only afford a $2,000 per year gardening budget, it’s unrealistic to hope that you’ll have a $100,000 landscape at the end of your five- year plan. Better to have a lush bed of pachysandra sparked by containers of colorful annuals than acres of mulch beds with scraggly trees, shrubs, and perennials.

In design terms, editing usually means taking something out, but it can also mean moving things around, so that the overall design flows more smoothly. This can apply to hardscape, garden ornaments, activity areas, and plants.

Think about the best use of your various garden spaces right now. Then start editing to bring that vision closer to reality.

Gardening as Process: Gardening Resolutions for 2009

Whether your garden is old or new, part of the planning process needs to be defining your destination so that you not only know how to get there, but also when you’ve arrived. And many of us don’t get more than six to eight months to do it, because our “year” is the growing season. So let’s get started!

Stuff happens. This fall, a 75-foot wild cherry tree blew down across our newly-installed rhododendron garden on the east side of the house, taking with it the deer exclosure and our electric and telephone lines. After Dan lopped off the top of the tree and repaired the fence, I crawled around on the trunk and noted that, if he cut off another piece small enough to carry away, the remaining trunk would crush nearly every one of the 12 large rhodies we’d just planted! No problem. Come spring, we’ll dig out all the plants that are at risk, cut up the tree, then put the rhodies back. At least we don’t have to dig new holes.

Next on my agenda (but not Dan’s) is the lavender garden expansion out front. Sounds easier than it is. This is the area where we moved the propane tank back by about ten feet in October. Some basic work needs to happen here, such as installing a step or two to get down to the tank and stabilizing the earth around it. My winter planning on this area consists of figuring out how the rock wall that will be placed in front of it should look, so that Dan can build it as soon as the weather breaks. Right now we’re considering a double wall that could act as a container for plants. Hmmmn. What kind of plants?

Well, the existing lavender patch will have to be enlarged out to meet the new wall. Other shrubs, or small trees under consideration for propane tank camouflage are red twig dogwood, dwarf Harleson (also called Harelson) and Winesap apples, roses, creeping juniper, switch grass, white forsythia, or some of my volunteer white cedars. The space cannot accommodate all of these plants, so there are tough decisions to be made--- part of the fun of creating your own environment.

We brought home ten dwarf conifers from the Garden Writers’ Conference (thanks, Iseli Nursery) that need homes; the lily bed needs enhancement, and some more ferns are needed for the white-and-fern garden.

Next, growing more veggies. Cherokee purple and hybrid cherry tomatoes are back on the list, as is my Galeux d’Eysines pumpkin (great soup!), and moving more strawberries from the east garden to the west berm. I want to try some cucumbers and, maybe, some beans.

High on the perennial list are candelabra primroses to skirt the front of the water fountain. This has been a problematic space --- wet or dry shade, depending how often I remember to turn on the fountain. And a puppy that pulls the plants out when my back is turned. Whirlwind hosta has done very well there, near the back corners, but I still want some flowers that are not impatiens.

You may have noticed several things about my gardening resolutions: There’s more than two people can do in the time available; we ‘extend the season’ by scheduling building projects in spring and fall; nature supplies an abundance of hard labor due to unforeseen weather “events;” a gardener’s work is never done. That’s why gardening is a process, not a project.

Have fun coming up with your own gardening resolutions for 2009.