Tree · Juglandaceae
Pecan
Carya illinoinensis
Give it room, full sun, and a pollination partner, and a pecan shades the yard for generations.
Full sun
Every 7–14 days
USDA 6–9
66–131 ft · 20–40 m
Overview
A pecan is a long-lived shade tree that happens to hand you a nut crop. It belongs to the walnut family and is native to the river valleys of the south-central United States, where it grows into a broad, towering canopy. Plant one and you're planting for decades, since a healthy tree can stand for a hundred years or more.
Size is the first thing to plan around. A mature pecan reaches 66 to 131 feet (20 to 40 m) tall with a spread to match, so it needs open ground far from houses, walks, and power lines. The wood is brittle and sheds limbs in ice and wind, which is one more reason to give it space.
Nuts take patience and a partner. Pecans are wind-pollinated and time their pollen and flowers so a single tree pollinates itself poorly, which means two compatible cultivars crop far better than one. Add the tree's appetite for zinc and its long wait to first harvest, and a pecan rewards the gardener who thinks in years rather than seasons.
Care
The short version: full sun and deep, well-drained soil, with plenty of room for a huge tree. Water deeply but not often, feed with nitrogen and zinc through the growing season, and plant a second cultivar nearby for pollination.
Light
Pecans demand full sun to crop well, ideally 8 or more hours a day. A young tree tolerates a little partial sun, but heavy shade gives you a thin canopy and few nuts.
Water
Water deeply but not often, letting the top half of the root zone dry between soakings. Young trees need regular deep watering to settle in, and even mature trees want a long soak during nut fill and late-summer drought. Shallow, frequent sprinkling does more harm than good.
Soil
Give a pecan deep, fertile, well-drained sandy loam to loam. It shrugs off the odd flood but rots in standing water, and it likes a pH between 6.0 and 7.0, which also keeps zinc within reach of the roots.
Temperature
Pecans handle a wide swing, from about -4°F to 104°F (-20°C to 40°C), which suits the long, hot summers they need to ripen nuts. The deep cold tolerance lets them stand through winter once dormant.
Humidity
These trees grow fine across 40% to 70% humidity, so there's no number to chase outdoors. Warm, humid air does favor scab, which makes airflow and resistant cultivars matter far more than the reading itself.
Feeding
Feed from early spring through early summer with a balanced nitrogen fertilizer, then add zinc by soil or foliar spray. Zinc shortage is common in pecans and shows up as rosetted, crinkled new leaves, so build it into the routine.
Pruning
Prune in late winter while the tree is dormant. Train a young tree to a single central leader and cut out crossing, dead, or weak limbs; a mature tree needs little beyond clearing deadwood.
Repotting
Field-grown pecans aren't repotted, and a deep taproot makes them hard to move. Shift young nursery stock just once while dormant, and watch container trees for circling roots, stalled top growth, or fast-drying soil.
Size & spacing
Plan for a giant. A pecan climbs to 66 to 131 feet (20 to 40 m) tall with a spread of 39 to 75 feet (12 to 23 m), so set it far from buildings and lines and well apart from other trees.
When to plant
Pecans go in the ground while they sleep. Plant young dormant trees in late winter to early spring once the hardest freezes have passed, and the catkins follow in spring. The nuts ripen late, coming off the tree from October into November.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: late winter to early spring while dormant, after the worst freezes
- Harvest: wind-pollinated catkins and flowers in spring; nuts ripen and are harvested October through November
Hardiness
USDA hardiness zones: 6–9
Temperature: down to -23°C
Troubleshooting
Most pecan trouble comes down to wet-weather disease, a hungry tree, or sap-feeding insects. Catch the signs early on the leaves and developing nuts and you can step in before a season's crop is lost. Match what you see below, then act while it still helps.
Black sunken spots on leaves and shucks, with nuts dropping early
This is pecan scab, a fungus that takes off in warm, humid weather and is the main reason a crop fails in the wet Southeast. Spray on a protective fungicide schedule through the season, space and prune for airflow, and plant scab-resistant cultivars where summers stay damp.
Fix:
- Apply recommended fungicides on a protective schedule during the growing season
- Improve air movement by proper spacing and pruning
- Plant scab-resistant cultivars in humid regions
Crinkled, yellow-mottled new leaves bunched into rosettes
Pecans run short on zinc on sandy or high-pH soils, and the shortage shows first as crinkled, bronzed new growth crowded at the branch tips. Spray foliar zinc on the fresh growth in spring and correct the soil to match a test. Keeping the soil near pH 6 to 6.5 lets the roots take up zinc on their own.
Fix:
- Apply foliar zinc sprays to new growth in spring
- Correct soil zinc per soil test recommendations
Sticky leaves, black sooty mold, and early leaf drop
Pecan aphids feed on the leaf undersides and coat everything below in sticky honeydew that turns to sooty mold. Let lady beetles and lacewings do the work, and reach for a targeted insecticide only when numbers climb high enough to strip foliage. Going easy on nitrogen keeps the soft new growth aphids favor in check.
Fix:
- Encourage natural predators such as lady beetles and lacewings
- Use targeted insecticides only when populations are damaging
Toxicity
Pecan kernels are a safe, well-loved food for people, and the tree itself is fairly low risk. The catch is moldy fallen nuts, which can carry tremor-causing mycotoxins, and the rich fat of whole nuts that upsets pet stomachs. Rake up the drops and keep pets from scavenging, and the worry mostly disappears.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds
Safe for
People
Cats Mild
A cat that nibbles a fallen nut may get an upset stomach from the rich fat. The real worry is a moldy nut, since the mycotoxins it carries can trigger tremors or worse.
Dogs Mild
Dogs are the most likely to scavenge windfall nuts, and the high fat can bring on vomiting or diarrhea. Watch closely for trembling or unsteadiness, which point to a moldy nut and need a vet.
Horses Mild
Fresh nuts and leaves rarely cause much trouble, but moldy fallen nuts mixed into feed or pasture can carry the same tremor-inducing mycotoxins. Keep the ground under the tree cleared where horses graze.
Rabbits Mild
A rabbit gut is built for greens, not fatty nuts, so even a fresh kernel can upset digestion. Skip pecans as a treat and keep fallen, moldy nuts out of reach.
Livestock Mild
Cattle, goats, and sheep grazing beneath the canopy can pick up moldy windfall nuts, and the mold toxins are the concern rather than the tree itself. Clear drops from grazed ground.
Birds Mild
Backyard hens may peck at split nuts on the ground without harm, but moldy ones carry the same mycotoxin risk. Rake up drops so nothing rotten gets eaten.
People Safe
Ripe pecan kernels are a well-loved food and safe to eat. Just don't eat nuts that have gone moldy on the ground, and keep them away from pets.
Keep fallen nuts raked up so pets cannot scavenge moldy ones; the fresh kernels are not considered highly toxic but the high fat content and obstruction risk make them unsuitable as pet treats.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
United Kingdom
Animal PoisonLine: 01202 509000 (fee applies)
Australia
Animal Poisons Helpline: 1300 869 738
Varieties
Pecan cultivars are sorted by when they shed pollen and how well they fend off scab. These are the names you'll meet most often, and pairing two of them is what fills the crop.
Pawnee
A Type I cultivar that ripens early, which makes it a smart pick at the northern edge of pecan country.
Desirable
A Type II cultivar prized for large, top-quality nuts, though it catches scab badly in humid regions.
Elliott
A Type II cultivar grown across the humid Southeast for its strong resistance to scab.
Stuart
An old, widely planted Type II cultivar trusted for steady cropping and fair scab tolerance.
Companions
Plant near
Crimson clover or other legume cover crops: Cover crops between rows add nitrogen, reduce erosion, and support beneficial insects in orchards.
Keep apart
Tomato: Pecan produces juglone (milder than black walnut), which can stress juglone-sensitive plants like tomato grown directly beneath the canopy.
How to propagate
You don't grow a named pecan from a planted nut. Cultivars are grafted onto seedling rootstock, while seed itself is grown mainly to raise that rootstock.
GraftingDemanding
Late winter to spring for whip and tongue or patch budding in summer · Named cultivars graft onto seedling rootstock and begin bearing in roughly 4 to 8 years
Named pecans don't come true from seed, so growers graft or bud them onto vigorous seedling rootstock. Do the whip and tongue grafts from late winter into spring, or patch bud in summer, and a grafted tree starts bearing in roughly 4 to 8 years.
SeedModerate
Stratify nuts over winter and sow in spring · Seedlings used mainly as rootstock; seedling-grown trees are variable and bear after many years
Growing from seed is how you raise rootstock, not how you copy a named cultivar. Chill the nuts over winter and sow them in spring, but expect seedling trees to come out variable and to make you wait many years for nuts.
Myths
A single pecan tree will reliably crop on its own.
Pecans are wind-pollinated and split their timing, so a Type I tree sheds pollen before its own flowers are ready and a Type II tree does the reverse. Plant both types nearby and cross-pollination lifts the yield well past what one lonely tree can manage.
All pecans are dangerously poisonous to dogs.
Fresh kernels aren't highly toxic, though whole nuts can cause an upset stomach or a blockage and pack a lot of fat. The real danger is moldy nuts, which can hold tremor-causing mycotoxins, so the fix is raking up the drops rather than fearing the tree.