Rocky soil lacks nutrients and has poor water retention, a combination that doesn’t work well for most trees. Nonetheless, rocky soil shouldn’t stop you if you still want trees in your garden.
You can find tree varieties that flourish in rocky soil. Such trees have shallow root systems that allow them to access moisture from the ground. Below are tree varieties that do well in rocky soil.
Fir
Fir is an evergreen coniferous tree found in the mountainous regions of Africa, Asia, Europe, Central America, and North America. These trees thrive in rocky gardens, provided they are in full sun and the soil has some moisture.
The roots of fir trees don’t spread laterally. Instead, they venture deep into the soil, allowing fir trees to maximize moisture absorption. Fir trees have a spread of about 20-25’ at maturity.
Maple Tree
Maple trees do well in rocky soils and thrive in the sun or partial shade. The roots of maple trees spread laterally across the soil, extending as far as 25 feet. Ensure you keep these trees about 30 feet from your house and plumbing system.
You can choose from more than 70 species of maple trees. Of all species, the Rocky Mountain maple does well in rocky yards. If your garden has bedrock and shallow soil, maple trees will not survive.
Birch
If you have rocky soil and live in the northern parts of the US, the birch tree is the best choice for your yard. The birch is a deciduous ornamental tree that thrives in the arctic temperatures of the north. These trees have shallow root systems, making them ideal for rocky soils.
That said, birch trees need plenty of water at the beginning. They also require more ground cover (which you can achieve through mulching) to protect the root system. Although it’s drought-resistant, the birch tree does better in cooler northern temperatures. It would struggle in the hotter south.
Aspen Trees
Although aspen trees grow in any soil type, they do well in gravelly and rocky soils. The aspen tree is native to Canada but does well in the Northern USA. It thrives in northern climates with cool summers.
The aspen tree is low maintenance and can regenerate from shoots. Its roots spread laterally, and new trees may grow from them. At maturity, aspen trees have a spread of about 20-30’.
Olive Tree
What better way to utilize your rocky soil than with a fruit tree? Olive trees are great ornamental and fruit plants that adapt well to rocky soils with good drainage. Their leaves spread out to about 20 feet.They also do not require a lot of nutrients (except nitrogen) for them to flourish.
Another advantage of planting olive trees is their resiliency and resistance to pests and diseases. However, you’ll want to watch out for fungus and keep your olive trees well-pruned.
Fig Tree
The fig tree is another fruit tree that does well in rocky soils. Fig trees love full sun and well-drained soils, similar to what you’ll find with rocky soil. Like other trees in this list, the fig tree has a shallow root system, making it perfect for rocky soils. That said, some fig varieties have roots that go deeper into the ground.
A sunny spot in your rocky garden is perfect for growing a fig tree. Fig trees usually grow wider rather than taller, so you should leave enough room for them to spread.
What To Do Before You Plant Trees in Rocky Soil
As you’ve seen, you can still use your rocky garden by growing trees. But before you start growing them, you should look at a few factors, including the climate zone of your area.
While these trees may grow in rocky soil, they will not be successful in climates unsuitable for their growth or survival. Do proper research beforehand so your efforts aren’t wasted.
Check whether your area has a rock bed and how deep into the soil it is located. Most trees, even the ones that do well in rocky ground, won’t grow if the rock bed is too close to the surface. And, while at it, add some plants that do well in rocky soils to complete your garden.