What Environment Do Cashew Trees Grow In? Climate, Soil and Conditions

Cashew trees grow best in a warm tropical climate with a clear dry season, in sandy, well-drained soil, at fairly low elevations and with no frost. They're tough trees that do well on land many other crops struggle with, but they're particular about two things: warmth all year round, and a dry spell when they flower.

Cashew trees do best in roughly 20 to 30°C, and they need the weather to stay warm through the year. Frost damages them, which is why cashew is grown in tropical regions near the equator and not in cooler climates. In Sri Lanka, the warmth is never the problem.

Cashew trees are usually grown where annual rainfall is somewhere around 1,000 to 2,000 millimeters, but what matters just as much is when it falls. They need a distinct dry season of several months.

The reason is flowering. The trees flower and set fruit during the dry period, and heavy rain at that time can wash away blossom and encourage disease, which means fewer nuts. A dry spell while the nuts form and mature gives a better harvest. Too much water around the roots is also a problem, because cashew trees dislike waterlogged ground.

Cashew trees like deep, sandy or sandy-loam soil that drains well, and they prefer it slightly acidic. Compacted or waterlogged soil is the main thing to avoid.

They also tolerate poor soil better than most crops. That's a big part of why cashew has long been planted on dry, sandy, marginal land, which we cover in our post on the history of cashew in Sri Lanka.

Cashew generally does best at low elevations, from near sea level up to a few hundred meters, although it can be grown higher in some places. It's also a full-sun tree. It wants open, sunny ground and plenty of light, not shade.

Put those conditions together and Sri Lanka's dry zone is a natural fit. It's warm all year, receives roughly 900 to 1,500 millimeters of rain, mostly from the monsoons, and has a long dry stretch. Cashew grows across much of the dry zone, with Puttalam one of the most important districts.

Flowering starts around November and runs into the early months of the year, and the harvest typically comes in the first half of the year, mainly around March and April. We source our cashews from farms in Puttalam.

Because cashew is so tied to the seasons, an unusual year can change the harvest. Unseasonal rain during flowering, or a very hard drought, can cut how many nuts a tree produces. A smaller harvest means less supply, which is one of the reasons cashew prices move through the year. Our kaju price guide explains the other factors.

Once the nuts are harvested, there's a lot of work before they reach you. We walk through it in how Sri Lankan cashews are roasted. When you're ready to taste the result, you can browse our cashews.

If you enjoyed this, you might also like our guides to how a cashew is grown and processed.