How Many Walnut Trees Should You Plant Per Acre?

Are you considering planting walnut trees on your land but unsure of how many to plant? You've come to the right place. Whether you have a small space or you are planning to commercially grow walnuts on large acres of land, we've got you covered. In this article, you'll get all the information you need to determine the ideal number of walnut trees to plant per acre.

For small farms, you can plant 20 walnut trees per 0.4 acres or less, spaced 20 feet apart. For medium farms, using the 28-foot spacing, you can fill an acre with 56 trees. For large-scale farms for wood production, you can use the 8 x 8 ft spacing to have 681 trees, or 17 x 17 ft to have 151 walnut trees.

When deciding on the spacing between your trees, you may want to consider the size of the farm you want to operate, as well as the species of walnut trees you will grow. Let's learn how these factors affect the number of walnut trees per acre as well as other planting considerations.

Determining how many walnut trees to plant per acre is a key decision that will shape the layout and potential productivity of your orchard, as you embark on the exciting journey of starting a walnut farm from scratch.

Optimal Number of Walnut Trees per Acre

Generally, about 20–30 walnut trees can be planted in less than an acre, with each tree spaced at least 20 feet apart. However, this number of walnut trees per acre can vary depending on the size of your farm and your goals.

A higher density of trees per acre will maximize early yields while using up land more efficiently. On the other hand, lower-density planting will support better tree growth and long-term productivity. You may need to make sure that your walnut trees are planted on soil with good drainage, a pH between 6.0 and 7.0, and plenty of organic matter.

Below, let's take a look at how many walnut trees you can plant for different farm sizes, considering tree density and spacing.

Tree density in small-scale walnut farms

For a small-scale walnut farm, you may want to start with around 20–30 walnut trees per 0.4 acres or less, ensuring each tree is spaced at least 20 feet apart. At this size, you can manage your farm more easily and become familiar with growing walnut trees.

There are several walnut tree species to choose from, including black walnut, English walnut, and Carpathian walnut. Factors such as soil, climate, and target market affect which species are most suitable for your farm.

Tree density in medium-sized walnut farms

As you progress to a medium-sized farm, you can increase the number of trees per acre. For example, planting distances of 28 feet x 28 feet result in 56 walnut trees per acre. This provides better light exposure and increased yield potential for your walnut trees.

When selecting tree species for a medium-sized farm, you may still want to consider the different types of walnut trees, but you will also need to focus on the specific tree growth requirements for their optimum development and production.

Tree density in large-scale walnut farms

For large-scale walnut farms, you may want to consider higher-density planting, such as 8x8 feet spacing resulting in 681 trees per acre. Doing so is especially common when growing walnut trees for wood. If your primary goal is nut production, a spacing of 17x17 feet with 151 trees per acre is more appropriate.

At this scale, you need to find the ideal balance between tree growth, cultivation costs, and maximum yield by carefully evaluating the best walnut species to match the soil and climate conditions.

The Species of Walnut Tree Affect the Number of Trees per Acre

Different species of walnut trees have different planting density requirements, and this can affect the number of trees allowed per acre. Let's discuss the characteristics of three of the most popular walnut tree species:

Black walnut trees require plenty of space to grow

Black walnut trees (Juglans nigra) are native to North America and produce high-quality wood in addition to their delicious nuts. These trees can grow up to 50 feet high, requiring plenty of space to grow.

Based on various planting densities, you may plant anywhere from 20-30 Black walnut trees per acre, considering a spacing of 20 feet apart or even up to 436 trees per acre if you want a high-density plantation with a spacing of only 10 feet x10 feet.

One thing to keep in mind when planting that black walnut trees is that they produce a chemical called juglone, which can be harmful to some plants, so plan the plants around your walnut trees carefully.

English walnut trees require less spacing to grow

English walnut trees (Juglans regia), also known as Persian walnut trees, are well-known for their thin-shell nuts commonly found in grocery stores. These trees have a slightly smaller stature than black walnut trees but still require space for growth.

When planting English walnut trees, you can grow as many as 182 trees per acre, with planting distances of 8 feet between the trees in the row and 30 feet between the rows. You may also opt to adjust the planting density to suit your specific needs. English walnut trees prefer a temperate climate with mild winters and long, warm summers.

Carpathian walnut trees require just enough space for growth

Carpathian walnut trees (Juglans regia 'Carpathian') are a subspecies of the English walnut tree and are prized for their cold hardiness, making them an excellent choice for colder climates. These trees can grow to a similar height and width as the other walnut species and produce large nuts with thick shells.

If you opt for these species for your walnut farm, you may use the same planting densities as English walnut trees (around 182 trees per acre) or adapt the spacing to match your specific goals and land availability.

Tree Spacing Determines the Number of Walnut Trees in an Acre

Let's discuss the difference between row spacing and tree spacing within rows so you can further plan out the number of trees you want to grow on your walnut farm.

Row spacing on your walnut farm

When laying out your walnut orchard, you may want to start by determining the appropriate distance between rows. Row spacing allows for equipment access, air circulation, and sunlight penetration, which helps promote tree health and fruit production.

For small and medium walnut farms, you need to aim for a row spacing of about 20 to 24 feet apart. Large walnut farms may require a row spacing of 30 to 40 feet to accommodate larger equipment and more extensive orchards.

Tree spacing within rows

Next, you could also consider the distance between the trees within the rows. Tree spacing affects overall tree health and productivity, so it's important to get this right.

You may want to plant English walnut trees 20 to 25 feet apart within rows, while black walnut trees should be planted 40 to 50 feet apart, as their root system may release chemicals toxic to other plants.

As you decide how many walnut trees to plant per acre for optimal orchard density, it's crucial to also consider the expected walnut yield per hectare and its potential profit, ensuring your planting strategy aligns with your financial goals.

Planting Considerations When Planning for a Walnut Farm

Choose the right planting site

You may choose a location that has enough space to accommodate the desired number of trees and their spacing requirements. For instance, black walnut trees should be planted 40'–80' apart, while English walnuts require a spacing of 20'–40'. Your goal should be to optimize the number of trees per acre, accommodating around 20–30 trees for a well-spaced walnut farm.

Ensure the correct soil type and provide proper fertilization

Walnut trees can grow in a variety of soil types, but they prefer well-drained soils rich in organic matter. The ideal soil pH for walnuts is between 5.0 and 7.5. Fertile soil can optimize the growth and productivity of your walnut trees. You may want to conduct a soil test before planting to ensure the necessary nutrient levels are present in the soil.

Provide adequate water source and good drainage

Walnut trees have high water requirements, especially during the summer months. However, they are sensitive to overwatering and poorly drained soils. Strive to maintain an adequate soil moisture level without creating waterlogged conditions, as excessive water can lead to root rot and decrease oxygen availability for the root system.

Consider the sun exposure and climate of the planting site

Walnut trees thrive in full sun and require at least 6–8 hours of direct sunlight per day. Additionally, walnut trees are sensitive to frost. Try to choose a location with a climate that is suitable for walnut cultivation, keeping in mind that late spring frosts can damage the young walnut trees and impact the overall productivity of your farm.