Have you ever wondered what edible plants you can grow if you are trying to plant them near walnut trees? Black walnut trees are infamous for putting out a chemical that will kill off many other plants as a way of ensuring its own survival– so you need to choose what to grow near one with care. Let’s look at 19 edible plants that can grow near walnut trees.
There are lots of vegetables that you can grow near black walnut trees, including things like parsnips, beets, carrots, onions, corn, melons, squash, beans, lima beans, snap beans, cherries, and black raspberries.
Let’s look at growing edibles near a black walnut tree in more detail. We’re going to find out what you can grow and how to grow it, as well as briefly covering which plants won’t grow near a walnut tree and why.
Why Do Black Walnuts Cause Growth Issues?
Black walnuts cause growth issues because they emit a chemical called juglone. This is intended to kill off other plants, reducing the amount of competition that the walnut faces and ensuring that it can get all the resources it needs. Juglone is toxic to plants even in relatively low doses, and plants that are sensitive to it can be killed within weeks.
Juglone can also remain in the soil long after the walnut tree has been removed, so just getting rid of the tree will not be sufficient for solving the issue. If the roots remain in the soil, they will continue to output juglone as they break down, causing disruption to the surrounding plants and poisoning any that are sensitive to the chemical.
Plants that are suffering from juglone poisoning tend to wilt, gradually turning yellow and floppy. They will die soon after. It is thought that the juglone prevents the plant from respiring properly, which robs them of the energy needed to take up water and nutrients from the soil. In species that are susceptible to juglone, this will often result in a quick death.
Many parts of the black walnut tree contain juglone, including the nut hulls, roots, and buds, and even the leaves and stems in smaller doses. You will need to plant any sensitive plants far enough away from the root network to be unaffected, and keep all decomposing parts of the walnut (such as fallen leaves) off the soil if you want the plants to keep growing. Don’t assume that plants are safe just because they are not under the tree’s canopy; juglone can spread through the soil for long distances.
What Edible Plants Can Be Grown Near Black Walnut Trees?
If you’re looking to grow some edibles in your backyard, their proximity to any black walnut trees is an important factor to consider. Ideally, you want to make vegetable beds a reasonable distance from the trees so you can plant without having to worry about them. However, if you can’t do this, you may want to grow things like:
- Beans (many varieties will grow)
- Melons (many varieties will grow)
- Squash (many varieties will grow)
- Black raspberries
- Wild yams
- Jerusalem artichokes
As you can see, there are quite a few edible plants that will grow well around a black walnut tree, but you are much more limited than if the tree is not present, so choose with care. If none of the above crops appeal to you, you may need to choose a different position for your vegetable bed.
Many root vegetables will grow well beneath a walnut tree, but be aware that potatoes will not; they are sensitive to the chemical that the tree outputs, and will wilt and die quickly if they are exposed to it. A lot of gardeners get caught out by this because things like carrots will thrive – so make sure you are aware of it.
A lot of fruit bushes will tolerate the chemical, so these may be a good option if you are struggling to find other things that will grow. You can also grow some kinds of grains, including wheat, near a black walnut, and there is some evidence to show that walnut trees can actually increase the growth rate of some kinds of small grains. We’ll look in more detail at some of the edible plants below.
Carrots And Parsnips
Carrots and parsnips should grow well near a black walnut and they are popular crops to choose. However, you need to make sure that they have enough space underground to grow; if there are walnut roots directly below where you have planted them, you will get stunted or twisted vegetables, because they will be forced to try to grow around the roots.
Before planting them, you should therefore dig down a little way to check for roots, particularly if you are working close to the tree’s trunk. If you are further away, roots are unlikely to be a major problem.
You also need to make sure that the carrots or parsnips are going to get enough light, as they need at least 6 hours of sun each day in order to grow well. You cannot plant them beneath the tree’s canopy therefore; they won’t have enough light to grow. Plant them further away from the walnut and they should flourish.
Corn takes up a lot of space in a backyard, but it’s a delicious crop and it will tolerate the chemical produced by the walnut trees well. It does need plenty of sun, however, so you will again need to plant it outside of the tree’s shadow if it is to survive and produce cobs. Don’t put it under the tree’s canopy.
Squash plants need a little less sun than the other crops. They do still require about 4 hours per day however. If you’re looking for a crop that you can grow under the canopy, they may not work, but if you plant them around the edges, they can sprawl underneath, using up the space and still getting enough light to be productive.
You can also try planting them under the canopy, but you may find that they struggle to get enough light, and don’t produce good crops as a result. It’s better to maximize their light if you can.
Like squash plants, melons need a reasonable amount of light, and will struggle if they are grown in dense shade. Again, try planting them along the edges of the canopy so they get plenty of sun, but they can sprawl beneath it and use up some of the otherwise wasted space there.
Beans will grow well near walnut trees, and you may wish to have them climb up your corn crop if you’re growing one. This pairing tends to work well, as the beans provide the nitrogen that the corn needs, while the corn will support the beans and help them stay upright. Both will survive the presence of a black walnut tree pretty well.
Onions also prefer to be grown in the full sun, not shaded by other plants. You should plant them outside the tree’s drip line so that they don’t get overshadowed by it. However, they will be unbothered by the tree’s chemical, and they are generally a hardy crop that will thrive in most conditions.
Beets will grow in partial shade, so they may be suitable for planting under the canopy of the black walnut. However, they do need to be able to push their roots down to at least 6 inches (some can grow as much as 48 inches down) so you need to check that there are no roots directly below your sowing line.
Beets are a great crop for filling in the space beneath the black walnut, although they do like to have some sunlight. Don’t plant them in full shade, or they are unlikely to grow.
What Edible Plants Cannot Be Grown Near Black Walnut Trees?
There are a few edible plants that you should not plant near black walnut trees, because they simply will not be able to thrive there. These include things like:
- Sugar beets
- Apple trees
- Pear trees
If in doubt, it’s usually best not to put an edible near a black walnut, because it will not grow well, and will probably die in a few years. You may get some growth out of it for a short amount of time, but as the chemical spreads through the soil, you will see it start to wilt and die. Avoid putting unsuitable plants near walnut trees.
In this article, we’ve looked at 19 edible plants that you can grow near a walnut tree, and all of these should survive coming into contact with the tree’s juglone production. It is important to take other conditions into account too, including your soil type and the nutrients available, the level of sunlight, etc., but starting with this list increases your chances of successfully growing edibles near a walnut tree. Avoid planting things like peas, or members of the nightshade family near your walnuts.
- A Beginners Guide To Building Guilds On Your Permaculture Homestead - March 28, 2023
- The Resilient Farm and Homestead by Ben Falk - March 27, 2023
- The Good Life: Helen and Scott Nearing’s Sixty Years of Self-Sufficient Living - March 22, 2023