Selecting and Growing Nut Trees
Although we at NNGA are biased, nutgrowing is a very rewarding activity. For the suburban homeowner wanting to plant a few yard trees, choosing a nut species can provide a food source for years to come in addition to shade and beautification.
If one has a few acres, planting it in nut trees (especially combined with direct marketing to the public) can provide a significant source of supplemental income. Nutgrowing can be a full-time job with the right space and patience!
Below, you will find how to select, plant, and maintain your nut trees. You can find a glossary by clicking the highlighted words.
Although all temperate nut species can be grown in most parts of the continent, not all will thrive or produce nuts in each area. The goals of the homeowner, hobbyist, and professional nut-grower will vary significantly.
Yard plantings are often space-limited or potential spots are predetermined. Although in one’s lifetime it may not be as much of an issue, keeping a pecan or walnut tree a reasonable size will be more difficult than a most chestnut or hazelnuts (which are often shrubby.) If a site is pre-determined, and doesn’t get as much sun, hazelnuts should be considered.
For all, the nut species must be suited to location. For example, pecans will grow and produce a nice shade tree with beautiful fall colors anywhere in the country, but may not have the growing season to produce nuts if planted in the north. English walnuts tend to leaf out earlier in the spring than other nuts, so locations with late spring frosts can be damaging. Chestnuts generally demand an acidic soil.
But these species-specific traits can often be worked around. Some pecans are native to southeast Iowa, naturally tolerating a shorter growing season. There are English walnuts that tend to leaf out later in the spring. In addition, planting on north or east facing slopes can delay the process. And to get chestnuts to grow, only part of the soil needs to be amended to make it more acidic. In addition, for any species, several nuts can be planted, and one tree selected, for whatever trait is desired (cold tolerance, compatibility with local soils, etc.)
Choosing a Site
All nut trees love sun. Make sure your location has exposure to sunlight the majority of the day. Although the tree may grow in a shady location, it is not as likely to thrive, and will not produce as many nuts. If you have a shadier location you’d like to plant, consider hazelnuts. All nut trees also like to have well-drained soil. Even pecans, which are known to grow in river bottomlands, need to have their roots not be saturated in the growing season. Avoid locations you can picture holding water long after a rainstorm. Especially if you’re planting a nut tree as a yard tree, consider how close it is to structures. Most nut trees have the potential to get big if left unpruned.
If you are planting a bareroot tree, dig the hole large enough so the roots to the tree can be spread out without reaching the sides of the hole. If your soil is high in clay or sand, consider amending it with organic material such as compost or peat moss. No not add fertilizer to the planting hold of a bareroot tree as you may burn the roots. Backfill the hole with dirt or the dirt/compost/peat moss mixture, being careful to keep the root collar level with the surface, or barely below. Gently tamp down the soil to remove air pockets. Water to further settle the soil.
If you are planting a tree with an intact root ball and soil, the hole doesn’t have to be as big, and fertilizer (ideally a slow-release variety) can be mixed with the surrounding soil.
Spacing trees properly is important so that they have enough room to grow and produce nuts.
The trees on the left are too close.
When trees are planted too close together, depending on the species, they may shade each other and reduce nut production as with these chestnut trees.
The grower was probably planning to remove some trees, but never got around to do so and now the trees are growing upward and losing yield.
The trees above are properly spaced.
Trees were placed in the field and allowed to fill in their spaces without hindering the growth of other trees. Perhaps some trees were already moved or removed to allow the trees to grow larger. Flowering on these chestnut trees will take place across the entire surface area of the tree and yields should be high.
Maintain a weed-free zone
Especially in young trees, keep an area at least a few feet diameter around the tree trunk free of weeds and grass. Their roots are significant competition for young nut trees. This can be done with herbicides or various types of mulch (such as wood chips.) If you mulch, be sure to keep the few inches immediately around the tree free of mulch so as to not provide a haven for mice. Weed mats are also available which are materials, polymer or organic, that are placed around the tree to inhibit weed growth.
Consider irrigation and fertilization
Depending on your locale, irrigation can be a growth augmenter or a lifeline. Most trees will benefit from a fertilization regimen. Even if a tree grows without fertilization and/or irrigation, it may have more consistent yields if receiving supplemental water and fertilization. Growth will also be quicker with both. An irrigation system may also be a conduit for fertilizing, a process called fertigation.
There are several goals of pruning. Branches with narrow crotch angles or otherwise growing in a not desired direction can be removed. More sunlight can be allowed into the middle of the tree, promoting nut growth. A basic scaffold structure of the tree can be produced. A more extreme version of pruning and training trees is the practice of espalier.
Consider sunscald protection
As this most commonly occurs on the southwest aspect of trees, at least this area should be protected. Interior white latex paint, or various wraps, can protect the trunk.