How to grow a cashew tree from seed
Cashews (Anacardium occidentale) are tropical trees that grow surprisingly well from fresh seed. I've germinated them in my own South Florida backyard, and this is the same simple method I include with every order — no special equipment, just warmth, patience, and well-draining soil.
What you'll need
- Fresh cashew seeds — fresher germinates far more reliably than old stock.
- A sandy, well-draining potting mix (add perlite or coarse sand).
- Small pots or seed cells with drainage holes.
- A consistently warm, sunny spot (a windowsill, greenhouse, or outdoors in summer).
Step by step: germinating your seeds
1 · Soak the seeds
Soak your cashew seeds in room-temperature water for 24–48 hours before planting. This softens the hard shell and jump-starts germination. Change the water once a day. Seeds that float are usually duds — the ones that sink are your best bets.
2 · Plant shallow
Plant each seed about 2.5 cm (1 inch) deep in a sandy, well-draining mix, with the curved side down and the stalk end angled slightly up. One seed per pot avoids disturbing roots later.
3 · Keep it warm
Cashews love heat. Aim for soil around 27–32°C (80–90°F). A sunny windowsill, a warm porch, or outdoors in summer all work. Warmth is the single biggest factor in fast, reliable germination.
4 · Water lightly
Keep the soil lightly moist but never soggy — cashews hate wet feet. Water when the top of the soil dries out, and make sure every pot drains freely. Overwatering is the most common way to lose a seed.
5 · Be patient
Most seeds sprout in 1–3 weeks, though some take longer. Once a seedling appears, keep it warm and bright and protect it from any cold — the young seedling stage is the most vulnerable.
After it sprouts: caring for your seedling
Give it lots of light
Cashew seedlings want full sun. Indoors, use your brightest window; outdoors, ease them into direct sun over a few days so the tender leaves don't scorch.
Protect from cold
Cashews are frost-sensitive. Below about 10°C (50°F) they suffer, and frost will kill a young tree. If nights get cold, bring pots indoors or into a greenhouse.
Pot up as it grows
When roots fill the starter pot, move the seedling to a larger container with the same sandy, free-draining mix. Cashews have a long taproot, so choose a deeper pot rather than a wide, shallow one.
Where cashew trees grow
Cashews thrive outdoors year-round in USDA zones 10–11 — hot, sunny, frost-free climates like South Florida, where mine grow. In cooler regions you can absolutely still grow one: keep it in a large container, give it as much sun as possible, and bring it inside for the winter. With patience, a healthy tree can begin fruiting in a few years.
Common questions & troubleshooting
My seed hasn't sprouted — what went wrong?
Usually it's too cold or too wet. Make sure the soil stays warm (27–32°C / 80–90°F) and only lightly moist, and give it up to 3–4 weeks before giving up. Fresh seed and consistent warmth make the biggest difference.
My seedling is tall and floppy
That's a sign of too little light. Move it to a brighter spot or into direct sun (gradually) and it will firm up as it grows.
How often should I water?
Only when the top of the soil has dried out. Cashews are adapted to dry, sandy soils and rot easily if kept soggy — when in doubt, water less.