Improve the biodiversity of your yard, provide shade, and help protect against erosion—all in a smaller space than you think you need.
If you’re thinking of adding a tree to your landscape, whether you want to create shade, provide an animal habitat, or just for looks, there’s a better alternative you might not have considered. Rather than just one, why not plant a few trees spaced closely together? A "pocket forest" like this can add increase the biodiversity of your yard, provide runoff control for water, and cool the surrounding landscape. Here’s how they work, and how to go about planting one.
A pocket forest is a densely planted mini-forest that’s made up of multiple native species of trees. The goal of this compact forest is to add dense plants for shade, animal habitat, and erosion control to your yard. (If you don’t have space for trees, you can grow a thicket, or a densely planted grouping of native shrubs.)
Mini forests are also nice to look at, and they can improve the view and enjoyment of your yard without the intense maintenance required by a lawn. Although the initial investment in a pocket forest might be more than a lawn, they can save you money and time on maintenance while using less water.
A pocket forest can be planted in as little as 200 square feet of space, and though common wisdom says that trees can damage nearby structures, this is not always true, and depends on the species of tree and the growing conditions. With a little pruning, you can safely plant a variety of species relatively close to buildings as long as the trees are properly maintained.
In order to plant a pocket forest, you’ll need enough one and two-year-old native tree and shrub saplings to plant your area while leaving two to four feet between each specimen. If you plan to plant near a building, make sure to choose saplings that don’t have invasive root systems.
In order to determine what plants are native to your area, you can consult your local university extension. Your municipal government might also have listings for trees that are native to your location, and be able to recommend trees that are less likely to cause damage if you plan to plant them near a building.
Planting should happen during the dormant season in your area to allow plants to establish themselves. Dormancy occurs at different times of year and depends on seasonal temperatures and rainfall in your area, so consider this another opportunity to consult your local university extension for information particular to your climate.
If it’s not dormant season now, luckily there are some things you can do to prepare, like removing existing plants and planning your space.
Choose your space and measure it to plan for how many saplings you’ll need. Plants should be placed between two and four feet from each other, so you can estimate your plant spacing based on that. It’s a good idea to contact your local nursery at this point to let them know in advance approximately how many plants you’ll need and to make sure they have some in stock. At this point, you can also begin removing any existing plants from your chosen area to create optimal conditions for future planting.
Three months before planting, you should use the “lasagna method” to prepare the ground for your saplings and kill off any remaining plants. To accomplish this, lay down a layer of cardboard over the whole area, followed by a layer of leaf compost or leaf mold. Cover the compost with two to three inches of wood chips.
Now’s the time to pick your plants. Choose native plants that are appropriate for your area, keeping in mind the size of their root systems and sun needs. Since you’ll likely have a pretty big order, getting your plants a little bit ahead of time is a good idea.
Lay out your plants and arrange them so that they are between two and four feet apart to plan spacing, then then dig your holes and plant your saplings. Though small saplings only require a shovel’s depth hole, you can still save yourself some time by arranging your plants in their containers ahead of time so you don’t run out of space while you’re planting.
Once your saplings are in the ground, make sure to mark them with a surveyor stake or another easily recognizable marker for future identification and weed removal. This will help to keep from getting your sapling confused with a weed. You can also add some compost to the soil surface or use compost tea to improve the soil to give your new trees a boost.
You should perform structural pruning on your saplings as they grow, removing less healthy, lower branches and branches that are not able to support their own weight. Otherwise, your trees can be left to grow on their own. You can choose to take a hands-off approach to watering your growing pocket forest, knowing that a few of your saplings might die, or you can improve their chances by watering them for the first two or three seasons they’re in the ground. You shouldn’t need to water your native trees once they are established (that is, after the first three years).
