Oak trees provide ample amounts of shade beneath their green leafy canopies. You may find that the natural grasses in your yard tend to die out underneath your oak tree, or that patches of grass and weeds grow sparsely. So, you may be wondering: what grows under oak trees? Are there any shrubs or ground covers that thrive beneath spreading oak branches?
What You'll Learn Today
What Grows Best Under Oak Trees?
There are actually quite a few plants that thrive in shady conditions such as those found beneath oak trees. You simply have to know what you’re looking for.
Shade-loving perennials are the best types of plants to grow under oak trees.
Perennials come back every year so there’s no need to keep digging the area around the tree to plant fresh plants. Too much digging, or digging too deep, may disturb the tree roots and stunt the tree’s growth.
It’s best to plant perennials when the tree is young so they can grow together. That said, some types of perennials can be planted around mature trees as long as you are careful not to disturb the roots.
Most shrubs are perennials, and many of them love shade. There are many different types of shrubs you can plant, some of which are merely ornamental while others may bear edible fruits.
Again, it’s best to plant young shrubs around the same time you plant young oak trees. If you plant your shrubs later, they may not become as well established or may be stunted because the tree saps all of the water and nutrients from the soil.
That said, it depends on the type of shrubs you’re planting. We’ll discuss specific types of plants that grow well with oak trees in the next section.
If you don’t plant anything under your oak trees, you may find that wild ground covers such as clover and creeping charlie will automatically take over the area and start filling in bare spots.
You could let these wild ground covers do their thing, or you could be intentional and plant more decorative ground covers around your trees.
Ground covers are usually perennials or self-seeding annuals, so they come back each year without much effort on your part. They do well with oak trees because their roots are generally more shallow, so they don’t interfere with the oak roots.
There are many different types of grasses. If the grass in your yard has died out beneath your oak tree, that doesn’t mean all types of grass will do the same.
If you’re going to plant grass under your tree, the University of New Hampshire Extension suggests planting a shade-tolerant variety. Many decorative grasses and some types of lawn grass grow quite well in the shade and, thus, make ideal companion plants for oak trees.
Check out the following video for some tips on growing grass under oak trees.
Some mushrooms also grow well under oak trees. A few of them, such as oyster and lactarius indigo mushrooms, are edible and quite tasty.
Of course, if you’re unfamiliar with mushroom foraging, you won’t want to eat any of the mushrooms that come up under your oak trees. Some of them may be poisonous as well.
It’s also important to check on the health of your tree if you start noticing a lot of mushrooms, especially if you find them growing on or near the base of the trunk. In these cases, mushrooms might represent root rot or decaying wood.
Oak Tree Companion Plants
While many plants will grow in shade, good oak tree companion plants have to meet several criteria.
Oak companions must thrive in partial sun to full shade without robbing key nutrients from the soil. They should have shallow root systems that won’t damage the tree’s roots or steal all the water, but they must also be able to produce their own food from a relatively small amount of sunlight.
Some good perennials you could plant include:
- Holly – an ornamental shrub with dark green leaves and bright red berries.
- Shooting star – a shade-loving ornamental with white, lavender, magenta, or purple flowers.
- Grape hyacinth – a perennial purple-flowering plant that makes a good border around the oak canopy, as it needs partial sun.
If you want to grow shrubs, it’s best to choose plants that are native to your area. Depending on region, you may consider a few of these:
- Lilac – a shade tolerant shrub that produces sweet-smelling flower clusters.
- Bush poppy – a low-growing shrub that produces yellow flowers.
- Oakleaf hydrangea – a flowering shrub with leaves that will match your oak tree.
If groundcovers are more your thing, consider some of the following:
- Wintergreen – a vining ground cover that produces edible berries.
- Wild ginger – a vining ground cover with heart-shaped leaves.
- Bishop’s hat – a ground cover with small flowers of various colors.
If you want to grow grasses, a few to look into planting include:
- St. Augustine’s grass – a turf grass that thrives in shade.
- June grass – an ornamental grass with wispy seed heads that does well in dry, partially shady soils.
- Tufted hair grass – an ornamental grass similar in appearance to June grass that needs more moist soil conditions.
Can You Plant Azaleas Under Oak Trees?
Yes, azaleas are a good companion plant for oak trees. It’s important not to plant them too close to the trunk however, as they do need some sunshine to thrive best.
Also, keep in mind that azaleas can grow quite tall, sometimes as much as 10 feet. For planting under oak trees, you may want to stick with shorter varieties, especially if your oak has a lot of lower-hanging branches.
What Can You Plant Under a Live Oak Tree?
Like most other oak species, live oak trees grow quite large and produce a lot of shade. However, they tend to have much shallower root systems than other oaks.
With live oaks especially, it’s important to put your companion plants in the ground at the same time you plant your live oak, or else to choose companion plants with especially shallow root systems.
If you want to plant shrubs or other larger plants around your live oaks, be sure and plant them closer to the edge of the canopy rather than around the trunk to avoid damaging the roots.
Some good companion plants for live oaks include:
- Fremontia – a shrub covered in small yellow flowers.
- Monkey flowers – a vining shrub with bright multicolored flowers.
- Mahonia – a low-growing holly-like ornamental that produces blue berries.
What Vegetables Grow Under Oak Trees?
If you’re planning to plant a garden under your oak tree, you will inevitably face some challenges. Most fruit-bearing garden plants require copious amounts of sun and nutrients, and anything still growing in the fall is likely to get pelted with falling acorns.
That said, you may have better or worse luck growing vegetables under your oak depending on your location, the age and size of your tree, and the amount of nutrients and moisture in the soil.
Perennial fruits and vegetables tend to grow best under oak trees. Some you might try include ginger, pineapple, rhubarb, and horseradish.
An edible ground cover called longevity spinach may also grow well under oak trees. It is grown as a perennial in warmer regions and as an annual in cooler regions, as it is very frost sensitive. It thrives in partial shade and produces edible, semi-succulent leaves with a mild spinach flavor.
Some gardeners have had success with planting certain annuals under their oak trees. These shade-loving vegetables include tomatoes, asparagus, winter onions, and broccoli.
If you’re looking to plant shrubs or ground covers under your oak tree, it’s best to choose plants that thrive in the shade without stealing all the water and nutrients from the soil.
Ideally, you should plant your companion plants at the same time you plant your oak tree, but if the tree is already established, just be careful not to damage the roots when planting the companion plants.
If you are looking for more answers about oak trees, here is a guide to blooming oak trees.