When to Plant Walnut Trees (and How Far Apart)
When to plant walnut trees, how to plant them step by step, how far apart to space them and why you need two varieties.
Plant bare-root walnut trees while they are dormant – after leaf fall in autumn and before bud break in spring. Where winters are mild, late autumn to early winter planting lets the roots settle before growth begins; where winters are harsh, wait until early spring, as soon as the soil can be worked. Container-grown trees can go in at almost any time of year, but summer planting only works if you can water regularly. Space trees 7–10 m (23–33 ft) apart depending on the variety, and always plant at least two compatible varieties for pollination.
Autumn or Spring Planting?
Both seasons work. The right choice depends on your winter:
| Planting time | Best for | Advantage | Risk |
|---|---|---|---|
| Late autumn – early winter | Mild winters | Roots establish over winter; earlier start in spring | A hard winter can damage the young tree |
| Early spring | Cold winters | The sapling avoids winter frost | Planted late, it meets summer heat with weak roots |
| Container tree (any season) | Anywhere you can water | Roots are not disturbed | Summer planting needs frequent watering |
In the Southern Hemisphere the dormant window falls roughly between May and August. Whatever the season, never plant into waterlogged or frozen soil.
Choosing a Good Sapling
- Buy a grafted, named variety from a reputable nursery, with the variety written on the receipt.
- The stem should be straight, healthy and well hardened (woody).
- Roots should match the size of the top: a strong taproot plus plenty of fibrous roots.
- Reject plants with galls, rot or other signs of root disease.
- Check the graft union – the slightly swollen joint low on the stem – for cracks or separation.
A seedling grown from a nut will not be true to its parent and may take 12–15 years to bear, so it is a poor choice if you want nuts.
How to Plant a Walnut Tree Step by Step
- Prepare the ground. Walnuts need deep, well-drained soil – ideally at least 1.2–2 m (4–6.5 ft) deep. Avoid heavy clay, shallow soil and spots where water stands.
- Dig the hole. About 60 × 60 cm (2 × 2 ft) is enough. The taproot is long, so dig deep enough to take it without bending.
- Trim the roots. Cut back broken, crushed or very long roots with a clean cut.
- Set the depth. Plant at the same depth the tree grew in the nursery, with the graft union above soil level. Buried graft unions can root from the scion and invite crown diseases.
- Do not add fertilizer or fresh manure to the planting hole. If a soil test shows a shortage, phosphorus and potassium can be worked in beforehand; give no nitrogen in the planting year.
- Water in well – roughly 30–50 litres (8–13 gallons) per tree right after planting.
- Stake the tree. Young walnuts need support for their first 3–4 years. Tie firmly but check the ties regularly so they do not cut into the bark.
How Far Apart to Plant Walnut Trees
A mature walnut can spread 12–15 m (40–50 ft), so spacing depends on the vigour of the variety:
| Spacing | Trees per hectare | Trees per acre | Typical use |
|---|---|---|---|
| 10 × 10 m (33 × 33 ft) | 100 | about 40 | Very vigorous, large-crowned trees |
| 8 × 8 m (26 × 26 ft) | about 156 | about 63 | Traditional orchards, vigorous varieties |
| 7 × 7 m (23 × 23 ft) | about 204 | about 83 | Medium-vigour varieties |
| 8 × 4 m (26 × 13 ft) | about 312 | about 126 | Compact modern varieties |
| 7 × 3.5 m (23 × 11.5 ft) | about 408 | about 165 | High-density orchards with regular pruning |
Trees per hectare = 10,000 ÷ (row spacing × in-row spacing in metres). Run rows north–south where possible so trees get even light through the day.
Close spacing brings earlier returns, but walnuts keep growing. After 10–12 years crowded crowns shade each other, inner branches die, air circulation drops and diseases such as anthracnose and blight increase. If you plant densely, choose a compact, lateral-bearing variety and plan pruning from the start. In a garden, leave the tree enough space for its full adult size.
Pollination: Plant at Least Two Varieties
Walnuts carry male flowers (catkins) and female flowers on the same tree, but in most varieties they do not open at the same time – a trait called dichogamy. In many varieties the catkins shed pollen first (protandry); in others the female flowers are ready first (protogyny). A lone tree may flower heavily yet set few nuts.
Plant a second variety whose pollen release overlaps the main variety's female bloom. Common pairings include Franquette as a pollinator for Chandler, Fernor, Fernette and Pedro, and Meylannaise or Ronde de Montignac for Fernor. In orchards, pollinators usually make up about one tree in ten, scattered through the rows starting from the side of the prevailing wind, and no tree should be more than about 50–70 m (165–230 ft) from a pollinator.
Common Planting Mistakes
- Planting in a frost pocket or valley floor where late spring frost settles.
- Planting too deep and burying the graft union.
- Letting bare roots dry out between the nursery and the hole.
- Adding fertilizer or fresh manure to the planting hole.
- Planting a single variety with no pollinator.
- Planting too close to buildings, drains or a vegetable garden (walnut roots and leaves release juglone, which harms some plants).
Related Walnut Guides
- How to grow walnut trees: complete guide
- Best walnut tree varieties
- Where do walnuts grow?
- How often to water walnut trees
- How to prune a walnut tree
Frequently Asked Questions
What is the best month to plant a walnut tree?
In the Northern Hemisphere, bare-root walnuts are planted between November and April while dormant – late autumn in mild areas, March to April where winters are cold. In the Southern Hemisphere the equivalent window is roughly May to August.
How far apart should walnut trees be planted?
Vigorous varieties need 8 × 8 m to 10 × 10 m (26–33 ft); compact modern varieties can be planted as close as 7 × 3.5 m or 8 × 4 m with regular pruning.
Do I need two walnut trees?
For a good crop, yes. Most varieties shed pollen and receive pollen at different times, so a second, compatible variety greatly improves nut set.
How many walnut trees per acre?
About 40 trees per acre at 10 × 10 m spacing, 63 at 8 × 8 m, 83 at 7 × 7 m, and up to around 165 in high-density plantings.
Can you plant a walnut tree in summer?
Only a container-grown tree, and only if you can water it deeply and often through its first summer.
TarlaTapan guides focus on practical, field-tested growing advice. Corrections and suggestions are welcome at info@tarlatapan.tr.
