Walnut trees, most commonly English and black walnuts in the United States, are used most often for their nut production and sometimes timber. But how many walnuts grow on a tree each year?
On average, a mature walnut tree produces 50 to 80 pounds of unshelled nuts every year. Many species of walnut tree will begin producing at 7 to 8 years old but take until the 15-year mark to mature fully. Some walnut trees produce more heavily every other year as well.
We’ll be discussing how to plant and properly care for a walnut tree. This includes pointers to help your walnut tree grow! Alongside this, we will cover the full timeline of a walnut tree’s life.
Walnut Growing Season And Conditions
Walnuts have a growing season ranging from 140 to 150 days, beginning in late April or early May.
Most walnut trees require the temperature to stay above 27 to 29 ℉ while in the early stages of ripening. Walnut harvesting season is from mid-September through November.
You can tell they are ready for harvest when the hulls turn green, split, and start to fall naturally from the tree.
Despite this, there are some hardier species like the Carpathian English Walnut. These are better suited for harsh winter climates. The Common English walnut, butternut, heartnut, and black walnuts are more acceptable in milder and warmer climates. Be sure to choose the right species for your local climate!
How Long Does It Take To Grow A Walnut Tree? A Full Timeline
Say you find walnuts nearby. What’s next? How much time and care will go into growing it? How soon can you expect to harvest walnuts of your own?
While walnut trees are not the most complex to care for, they do require more attention than some others, like oak trees. However, walnut trees give back many times over in nut production what they require in care.
Starting from the top, or more appropriately the nut, let’s go through the full timeline of growing a walnut tree!
If you’d like to learn more about walnuts, read our post: 8 Differences Between Black Walnut Trees and Walnut Trees.
Day 1: Finding Viable Walnuts To Plant
The first step to planting your own walnut tree is finding viable walnuts. Identify a local species of walnut tree and wait for the perfect moment.
Collect your walnuts in the fall during their harvest season! Some walnuts, like black walnuts, need to be hulled and washed directly after collection. When doing so, wear protective gloves. Some walnut trees have toxic oils on their leaves and in their sap.
You might find something like the Large Nut Wizard useful for gathering numerous walnuts. You’ll need quite a few to get started, so collect as many as you see fit, within reason of course. It will also come in handy once your tree bears nuts for you to harvest in the future!
While you are washing your walnuts, discard any that may float. If walnuts float, they are underdeveloped or poorly filled. Poorly filled walnuts will not germinate properly, so keep an eye out for the ones that sink! They’ll be perfect to move on to the next step.
From the walnuts that sunk during washing, cut open a small sample. If they are full of solid, white meat, then they are viable. Non-viable walnuts will be beige and give off an unpleasant smell. Use this information to generate a percentage of viable nuts out of what has been collected.
If a large percentage of the harvested walnuts are viable, you will need fewer nuts per plot or container. Now we’re ready to move to the next stage of preparation, stratifying.
Day 1-120: Stratifying Your Walnuts
Stratification is an important, but not completely necessary, step to your walnut tree journey. It can be done in one of two ways.
Place your walnuts in a container filled with a mixture of damp sterile sand and peat moss. This aids in germination and will help ensure it is uniform later on. Place the walnuts in your mixture at 2-3inch layers and keep refrigerated for 90 to 120 days.
An example of moss would be Hoffman Canadian Sphagnum Peat Moss. It increases the amount of moisture your mixture will hold, as well as the time it will stay moist. When you’re keeping your walnuts moist for up to 4 months, dampening them less often definitely comes in handy!
While stratifying, you can use containers like coffee cans, plastic storage bags, buckets, and similar closed spaces. As long as they fit in your refrigerator, you can use them.
During this time, the sand and peat moss mixture must remain moist and cool.
The optimal temperature range for stratifying walnuts is 33 to 40 ℉. In terms of moisture, the sand and peat should be damp to the touch, but not soaked. Too much moisture may lead to molding.
This process can be done naturally as well, though it is less controlled. By planting in a similar mixture in the fall and leaving them throughout the winter, the walnuts will experience the same dormancy.
With this method, you risk a large freeze halting germination completely.
After stratification is complete, you can finally move on to planting your walnuts!
Day 1-120: Planting Walnuts In The Spring
According to the University of Missouri, there are multiple ways to plant your walnuts. These include planting in plots, creating a nursery, and planting in containers.
If you are going to plant in a plot, also known as in place, there is a bit of extra preparation. A seedbed for planting is the first step. It should be in an area that gets full sun.
You should also weed the area and keep it weed-free throughout the time it takes your walnuts to sprout.
After tilling and preparing the soil, dig 2 inch deep planting plots and place three to five stratified nuts per plot. Depending on the species, plots should be 20 to 80 feet apart.
The soil should be moist and kept moist for sprouting. Space out the walnuts in each plot as well as you will only keep the strongest ones in the future.
A nursery is another viable method for planting multiple walnut trees. Unlike planting in a plot, these will require transplanting later on. A seedbed is the first step in this method as well, though it will look slightly different.
Like before, till the soil and dig 2 inch deep holes for your walnuts. With this method, they should be 2 feet apart in rows that are a minimum of 4 feet apart.
Keep your nursery weeded and well-watered throughout sprouting and while growing your seedlings. You will transplant the seedlings the following year, which we will cover further down.
The last method, growing trees in containers, allows for the close monitoring of the nursery, with earlier and simpler transplanting later on.
Choose open bottom containers, the preferred type, or planters with sufficient drainage. The open bottom containers allow for air pruning, which helps prevent taproot circling. If you are using open bottom containers, place them on a wire bench to allow this air pruning to occur.
The potting soil you choose needs to allow free movement of water throughout the entire container. Mix in a slow-release fertilizer that will allow your walnut tree to get the proper nutrients for approximately seven to nine months.
Plant only one stratified nut per container and water daily. Container-grown trees require very careful attention and monitoring.
However, container-grown seedlings can be transplanted in the fall instead of the following spring. They can be held in containers over the winter, but be sure to keep the roots protected from freezing temperatures and insulated.
After the trees go dormant, cover them with an insulating cover or hay mulch.
Day 1- Year 1: Fertilization And Transplanting Of Your Seedlings
Keep an eye out for germination in four to five weeks. Your walnuts will begin sprouting and will require more attention.
Around mid-June in all cases aside from container planting, fertilize your seedlings with a slow-release fertilizer. Each plot should be fertilized in the first method, and fertilization occurs per row in the nursery method.
After fertilization, seedlings from the plot and nursery methods require watering once conditions become dry. Continue to water your container trees daily until transplanting. Any seedling area will need to be kept weed-free during this time as well.
For your container planted trees, the transplanting season starts three weeks to a month before the first killing frost and can continue into mid-November. If you keep them warm and covered as we discussed before, they can be held until the spring.
Weed and prepare the new planting location and start digging your walnut seedling a new home! The hole needs to be twice as wide as the root ball, and 16 to 18 inches deep, and spaced properly.
You should attempt to preserve as many roots as possible during this process. Space the holes according to the walnut species, though 30 to 50 feet is usually safe for planting at home.
Throughout this first year, monitor all of your nursery and plot seedlings to decide which ones you will keep.
The strongest growing tree at each plot, as well as your strongest nursery contenders, needs to be selected out of the bunch. Any other seedlings can be cut off below the root collar and disposed of.
You will transfer your nursery seedlings at the end of this section of the timeline. Once your seedlings are a year old, around March, the seedlings you choose to transplant need prepped.
To transplant, you will need to dig 16 to 18 inches deep around each seedling, preserving as many fibrous roots as you can.
The transplant process from here is the same as with the container-grown seedlings. Walnut seedlings will benefit from a layer of mulch 2 to 3 inches thick, kept away from the bark to prevent rotting.
Years 1-5: Growing Walnut Saplings
Once you have transplanted your saplings, the work gets lighter but does not end. Keeping the area weeded and properly watered is most important at this stage.
For the first 2 years, your saplings will need your help to get water regularly. You should water your seedlings as soon as the ground has dried completely around them. Deep watering, or watering down into the soil, will also be necessary periodically.
Deep watering can be done less frequently, around one to three times a month at the hottest point of the year, after the 2 to 3-year mark. The irrigation should occur about 2 feet deep around your tree. Walnut trees are not considered drought-hardy and benefit from this irrigation.
Pruning will also help your sapling stay healthy and grow through the early stages. This should be done sometime between the late summer and late fall. If walnut trees are pruned during the late winter or spring, it may cause bleeding or excessive sap flow.
When pruning, remove any damaged branches to prevent further spread. Thinning out crowded areas allows for more sunlight and air to reach the tree as well.
Years 5-15: From Seedling To Fruit Bearing Walnut Tree
Year 5 is the earliest your tree will begin producing nuts, though most start year 7 or 8. By the time you reach year 15, your tree should be in full production, providing the 50 to 80 pounds of nuts mentioned earlier.
When it comes to harvesting the fruits of your labor, you will know it’s time when the nuts begin to fall themselves. After you notice this, you can encourage the ripe nuts by gently shaking the limbs by hand or with something long and sturdy.
At this point, the nut collector you used to collect your initial walnut will come in handy again! After shaking, roll the cage along the ground, gathering the nuts. The quality of walnuts depreciates quite quickly, so be sure to collect them often.
Nuts lose quality faster inside their husks. If the husks remain after harvest, remove them manually. Easier to remove husks can be hand-peeled or rolled against a hard surface until they come free. For those that are harder to remove, dampen and store in an airtight container for 1 to 3 days.
All nuts need to be washed after their husks are removed to get rid of any remaining material. Walnut husks can stain your skin, so wear gloves!
Walnuts can then be dried in one of three ways between 95 and 105 ℉:
- Place on baking sheets outdoors: Make sure your trays somewhere they will receive plenty of sunlight (a southern wall preferably) and wait for 3 to 4 days.
- Dry on baking sheets indoors: They can be dried similarly indoors with low humidity.
- Place in an onion sack: Hang indoors, but be sure to shake the bag daily to rotate the nuts.
You can tell your walnuts are properly dried when the kernels and the packing material are brittle and break easily.
Once dry, you can store walnuts for 3 months to 2 plus years depending on the storage method. Always keep them stored in a cool, dry place.
At room temperature, walnuts will keep for 3 to 6 months.
To keep your walnuts good for even longer, store them at even lower temperatures. Below 32 ℉, they last up to a year. If you store them below 0℉, walnuts may stay good for 2 or more years.
Years 15-50: Maturing Walnut Trees For Timber
Other than just nuts, walnut trees are often used for their timber. Walnut wood is very hard and sought after for projects such as furniture building.
Your tree can fit the criteria for timber sale anywhere from 30 to 80 years after planting. The longer it is allowed to grow taller, the more it will be worth. Also, the straighter your walnut tree is, it is more likely to meet the proper standards for sale.
According to the Missouri Department of Conservation, there are two types of walnut wood quality. Veneer or lumber grade are the categories your tree might fall into.
The specifications for both are quite different, but veneer trees are much rarer, raising demand for them.
Consult a forester to assist you in identifying the value of your trees.
Your Results Walnut Disappoint!
Terrible puns aside, that’s all the information we have for now! Hopefully, you have a decent concept of what and how long growing a walnut tree takes.
With time and a bit of dedication, you’ll have walnuts to spare in the future!
You may decide to keep your walnut tree for many generations to enjoy. You might also decide to continue to plant and teach them how to sell their own trees in the future. Either way, your beautiful trees will provide for you and yours for many years to come.
Balandier, P., Lacointe, A., Le Roux, X., Sinoquet, H., Cruiziat, P., & Le Dizès, S. (2000). SIMWAL: a structural-functional model simulating single walnut tree growth in response to climate and pruning. Annals of Forest Science, 57(5), 571-585.
University, U. S. (n.d.). Walnuts in the Home Orchard. Extension.usu.edu. Retrieved November 4, 2021, from https://extension.usu.edu/yardandgarden/research/walnuts-in-the-home-orchard
Pecan and Black Walnut in Agroforestry Practices. (n.d.). Retrieved November 4, 2021, fromhttps://extension.missouri.edu/media/wysiwyg/Extensiondata/Pub/pdf/agguides/agroforestry/af1003.pdf
Le Dizès, S., Cruiziat, P., Lacointe, A., Sinoquet, H., Le Roux, X., Balandier, P., & Jacquet, P. (1997). A model for simulating structure-function relationships in walnut tree growth processes.
Selling Walnut Timber. (n.d.). Missouri Department of Conservation. https://mdc.mo.gov/magazines/conservationist/2013-02/selling-walnut-timber