Black Walnut
Also known as: Juglans nigra · Eastern Black Walnut · Southern Black Walnut
What's special about Black Walnut
Iconic native eastern hardwood — hard-shelled rich-flavored nuts and world-class dark timber. Northern and southern ecotypes available; strong juglone producer.
Growing this variety
Black Walnut follows the same growing basics as Walnut. Variety-specific maturity above; everything else below applies to the whole Walnut family.
Germination
Spacing & depth
How to plant
Plant fresh walnuts 2–3 in deep in a rodent-protected nursery bed in fall, or stratify in damp sand for 3–4 months and sow in spring. Walnut roots grow fast and deep — use tall pots or transplant young. Plant in permanent site before trees become root-bound.
Pre-sow treatment
Cold-moist stratify 90–120 days for stored nuts.
Grower's tip
Walnuts produce juglone, a compound that inhibits many other plants. Keep tomatoes, potatoes, and blueberries well away.
Woody plant facts
Soil preferences
Deep, well-drained native soil. Avoid amending the planting hole heavily — roots should learn to grow into the surrounding earth.
5.5–7.5 depending on species (conifers lean acidic; most hardwoods neutral).
Top-dress with compost and mulch in a wide ring; don't backfill with pure compost.
Watering
Deep soak weekly the first two years while roots establish; taper once the tree self-supports.
Slow trickle at the drip line, not the trunk. A 5-gal bucket with a pinhole is ideal.
Overwatered: yellowing, root rot, mushroom collar. Underwatered: leaf scorch, early leaf drop.
Prefers top-watering — Trees are always top-watered — deep slow soak at the drip line, never at the trunk. Bottom-watering only makes sense for nursery seedlings.
Temperature tolerance
Broad — most species tolerate 40–90°F once established
Down to species-rated USDA zone minimum
Hardy once established; young seedlings need protection their first winter.
Special germination requirements
Most temperate tree seed needs cold stratification (30–120+ days at 34–41°F) — see each species entry for the exact time.
Container growing
Possible with the right cultivar
Deep tree pots (root trainers) for the first 1–2 seasons; permanent site required for full growth.
Only dwarf, patio, or bonsai forms live long-term in containers.
Detailed harvesting
Not applicable for ornamental/timber trees. Nut and fruit species — pick when they drop naturally.
Post-harvest storage & preservation
Nuts: keep damp and cool, sow promptly. Winged/coned seed: dry, cool, dark in a sealed jar.
Culinary, medicinal & other uses
Shade, windbreak, wildlife habitat, timber, ornament, and long-term carbon storage.
Medicinal or traditional uses are shared for interest only — this is not medical advice. Consult a qualified professional before using any plant medicinally.
Seed saving
Wind- or insect-pollinated; seedlings rarely match the parent exactly (especially named cultivars — those must be grafted or cutting-grown).
Not practical for trees. Expect variation.
Collect fully ripe seed in fall, clean, dry or keep damp per species, then cold-stratify before spring sowing.
Your zone's planting calendar
Pick your USDA hardiness zone and we'll estimate the key dates for walnut in your area. These are regional averages — always check your own last-frost forecast before sowing.
My Black Walnut Walnut notes
Black Walnut Walnut seeds on hand
Track packets and loose seeds you already have. Private to your account.
Par level — leave at 0 for no alert. Anything below par shows on Seed Starting and your shopping list.
Order more seeds
Running low? Reorder from one of these seed stores.
Loading…
Other Walnut varieties
Heartnut
6–10 yearsHeart-shaped mild-flavored nut; attractive spreading tree with tropical-looking foliage.
Butternut
7–15 yearsNative eastern tree with sweet oily nuts in a sticky husk; slower growing and less common than black walnut.
Claro Walnut
6–12 yearsNative California walnut prized for high-quality timber and nuts; rootstock for commercial English walnuts.
Buartnut
6–10 yearsHardy butternut × heartnut hybrid — sweet mild nuts on a vigorous canker-resistant tree; good replacement for declining butternut.
Paradox Walnut
6–12 yearsVigorous hybrid (black × English) used mainly as commercial rootstock; fast-growing with excellent timber.