Walnut Fruit Guide

Walnuts are surrounded by round, green husks that are coarsely textured and about the size of a small apple.

How to Care for Walnut Trees


Mature nut trees need only dead and damaged materials removed through pruning each year. We offer pruning services for other fruit trees including apple, plum, cherry, and more. 


Fertilize yearly in the early spring. We offer compost tea fertilizing for fruit trees and gardens. Compost tea has many benefits, some of which are improved plant growth and increased nutrient retention.


Young trees need extra water to grow, while all fruit and nut trees need additional water during periods of hot, dry weather. Thoroughly soak the soil around your fruit trees every other week. Mulching around the base of your tree can help retain soil moisture as well.


When walnuts are ready, the husks surrounding them will begin to dry and crack and the walnut will fall to the ground. It is important to collect them regularly as they fall, as the nut quality will degrade quickly once on the ground. You can also gently shake the tree’s branches to cause walnuts to fall.

Walnuts are ready to harvest when…

  • Green husks darken and turn brown.
  • The husks crack and may peel away from nut easily.
  • The nuts fall from the tree.

Our FruitShare program does not have the capacity to harvest walnuts at this time!

Because walnuts must be harvested several times and the time-intensive nature of processing them, we are unable to provide harvest services for walnuts at this time.

Disease & Pest Control


Walnut Husk Fly

The major pest which impacts walnuts is the walnut husk fly. Female husk flies lay their eggs under the surface of the husk. The larvae feeds on the husk, causing it to soften and decay, as well as stain the shell and make the husk more difficult to remove. You can find out more information about the walnut husk fly here

The walnut husk fly can also damage peach, plum, pear, and apricot trees that are near the infested walnut tree, so it is important to treat for this pest if you have other fruit trees.

Storage Tips

  • Once picked or collected, remove the husk surrounding the nut to prevent the nut quality from degrading. Husks that are easier to remove can be peeled by hand or rolled across a hard surface to separate the husk from the nut. If husks are difficult to remove, the nut can be moistened and stored in a sealed container for 1 to 3 days, at which point they can be easily removed.
  • After removing the husks, all nuts should be washed  to remove any remaining husk material. 
  • Black walnuts contain dark dyes that will stain hands and fabric, so wearing gloves and old clothing is recommended during this process.
  • The de-husked nuts will then need dry, warm conditions for drying. They can be placed on a baking sheet in the sun or in a low-humidity, warm room for this. Optimal temperatures for drying are between 95° and 105° F. Drying can take 3 – 4 days. You can tell that a walnut has dried when the kernels and material between the nuts is brittle and breaks easily.
  • Walnuts can be stored in burlap bags, boxes, or barrels in a cool place or can be frozen.

There are two main types of walnuts grown in Utah—English walnuts and black walnuts. The roots of walnut trees produce a toxic compound called juglone, which can kill certain nearby plants.

Join the volunteer team!

We love our volunteers and would love to have you join us! There are many ways you can volunteer–from picking fruit to helping in a garden to sitting on a committee.