Growing a walnut tree from a seed requires a lot of time, instructions, and patience. They can be started from cuttings, or from a seed. Once they are mature, the black walnut tree can reach up to 100 feet tall with a large canopy of about 50 to 60 feet wide.
They can live for 200 years and are naturally grown in the central and eastern part of the United States. A walnut tree is not only good for producing walnuts, but they make a great shade tree, and provide bright foliage during the autumn season. Growing a walnut tree in a container can be done by following these steps.
Step One - Collect Seed
Walnuts will ripen and fall from the tree during September and November. This is the time when you should be out gathering them up. This is important as the fresher you can get the walnut, the better chances you have of it actually germinating.
Step Two - Soak Walnuts
Fill a bucket with water. Drop the walnuts into the bucket to soak for a few days. The water will soften up the husks which will need to be removed before planting them into the soil.
Step Three - Remove Outer Husks
For this step you will need to wear some old clothes and gloves. The outer husk of the walnut will contain a residue that will stain very easily. This stain does not come off quickly and can take some time to wear off. Remove the outer husk by tapping with a hammer until it cracks. Remove the seed.
Step Four - Choose Your Seed
After the husks are removed place the seeds back in the water. You will see that you will have some that will float and others that will sink. Choose the seeds that sink to the bottom of the bucket. These seeds will have a better chance of sprouting when planted.
Step Five - Stratify Seed
Walnut seeds need a period of 3 to 4 months to go through a process of stratification. This means they are placed in a cold area for this period of time to activate the germination. Place the seeds in a plastic bag and then in a cool place. This can not be interrupted at all. A refrigerator is a good choice.
Step Six - Plant Walnut Seeds
After the stratification period is completed you can now plant the seed in your potting soil. Fill a medium sized pot with potting soil. Place the walnut tree seed in the soil to a depth of one inch. After about five to six weeks you will the beginnings of your walnut tree sprouting from the soil. Continue watering to keep the soil moist and spread a little fertilizer around the trunk. Transplant the tree, soil and all, into a larger pot for continued growth.
Once the walnut tree has a trunk diameter of 3/8 inch you can transplant into your landscaping. Use the soil from the container as you replant the walnut tree.