If gardens could talk, oh, the stories they might tell. At my house, the tale would begin twenty years ago, when bulldozers came to clear an opening in the woods suitable for growing food. Seasons passed and the garden grew and prospered, but then personnel changes caused the plot to go through a fallow period. The space left to rest was quickly invaded by a legion of invasive plants, from privet to poison ivy, plus plenty of tree seedlings from the adjoining forest.
It doesn't take long for tamed space to go wild, especially in enriched garden soil. First come giant weeds and grasses, and then brambles and tree seedlings sneak in accompanied by invasive berry-bearing shrubs that are spread about by birds – multiflora rose, privet, autumn olive, and maybe some Japanese honeysuckle in the US, or rogue cotoneasters or rhododendrons in the UK.
Many property management guides will tell you to use herbicides to restore order to a neglected garden, but I don't think chemicals offer a sound solution. Besides, you can't get rid of established perennial and woody plants in one fell swoop. In my experience, it takes two to three years to clear overgrown space of unwanted plants and restore its ability to grow good vegetables.
Clearing Land by Hand
When clearing overgrown land by hand, the first things to go should be the woody trees and shrubs, which can be dug, hacked or pulled out if the trunks are less than 2 inches (5 cm) in diameter. First use a very sharp spade to dig around the plant and get an idea of its root structure. Then use a sharp hatchet to sever exposed roots. If the plant cannot be pulled by hand at this point, you can dig some more or use a Brush Grubber or similar device to pull the plants with the help of a vehicle or lawn tractor.
Whatever you do, do not cut off the woodies a few inches above the ground, where they will be a hazard to humans and lawn mower blades. If you can't pull out an established tree or shrub, saw off the stub as close to the ground as possible. Then use a drill to make several holes in the stump, and fill them with salt. The salt will help kill the stump, eliminating competition problems from roots that remain in the soil.
I once visited a man who had cleared a huge yard of woody plants by hand, and he showed me the spade he had used for most of the work. Between constant sharpening and wear from digging, what was once a standard garden spade looked like a child's shovel. As he said, it's great work if you can get it.
Brambles and vines are reasonably easy to dig out if unpleasant to handle, though you should expect to see them try to make a comeback from bits of root left behind in the soil. But the most persistent plants are usually tap-rooted perennial weeds such as docks, burdocks and thistles. Effectively managing established perennial weeds may take two or three years, because in addition to removing living plant parts, you must watch for new seedlings, which tend to be numerous for a couple of seasons.
Restorative Cover Crops for Cleared Land
Once unwanted plants are removed, the next step is to plant a vigorous yet easy-to-control cover crop in the reclaimed space, so it quickly forms a thick cover of vegetation. For example, you might use phacelia in spring, buckwheat in summer, or mustard in fall. As soon as the first cover crop starts to thin, take it down and plant another one. As you work, prepare to be humbled by the number of weeds and thug plants that have come back to life.
After three diggings and two cover crops, the soil can be shaped into permanent beds for long-term improvement, and you can grow undemanding crops like lettuce or bush beans. The overgrown garden is officially restored.
How to Deal With Woody Debris
The best thing to do with woody debris is to chip it, and renting a chipper may be worthwhile if you have a lot of slender saplings on your hands. Wood chips are my favorite material for paving around the composter and other mud-prone areas, and they are great for mulching blueberries and other plants that like acidic soil.
As for prickly brambles, I usually resort to partially burning them using a method that turns them into charcoal, or what some people might call biochar or agricultural charcoal. First I enlarge a hole already made from digging out say, a blackberry/burdock duo, and then pile some accumulated debris in the hole and set it on fire (under legally permissible conditions, or course). Then more debris goes on, and just when the fire really gets going I snuff it with soil, leaving the material to smolder. The fast fire leaves the half-burned bits and pieces riddled with holes, which makes them wonderful habitats for soil biota that work best with shelter, oxygen, and carbon together in one place. It's the best way I've found to turn thorny old blackberry canes into something good for my garden.
By Barbara Pleasant