Growing avocados as houseplants is child's play. Literally. What kid hasn't suspended an avocado seed over a glass of water in their class or as a home project, just to see what would happen? I think my entire first-grade class did this one year. (And now thinking back on it, I wonder what the adults did with all that avocado. Make a boat-load of guacamole perhaps?) Still, there's a reason we do this.
It's fun and it works. And although they are less exotic than they used to be, avocados still have those wonderful and imposing stones that, given enough time, will sprout into true avocado seedlings. And if you have enough patience, your seedling will eventually turn into an attractive little houseplant. True, it's unlikely your tree will every bear fruit (unless you have about ten years), and even if it does, the fruit from the child most likely won't resemble the original, but it's still a good time.
- Light: Like bananas, avocado plants thrive in full sun. If you're starting from a seed, the seed can be kept on a bright windowsill until roots form and the first leaves emerge.
- Water: Avocado plants should be kept continuously moist, but adequate drainage is essential. Watch for leaf yellowing, which is a sign of too much water. Also be careful to flush fertilizer salts from the soil.
- Temperature: Avocado prefer warm growing seasons, but can take winter temperatures down to 50˚F, when growth will slow.
- Soil: A rich, fast-draining mix is ideal.
- Fertilizer: Fertilize abundantly during the growing season with a balanced fertilizer. Fruit and vegetable fertilizer can be used after a few years when the plant is larger and nearing fruiting.
Avocado can be propagated in a number of ways. Professionals graft desirable avocado varieties onto disease-resistant stems to produce a disease-resistant tree with the desired kind of fruit. They can also be propagated by air-layering. In the home, the most common method is by seed. To sprout an avocado seed, insert three toothpicks into the seed and suspend it with the end down over a glass of water. Water should cover about an inch of the seed. Keep it in a warm place, but not in direct sunlight. The seed should sprout in two to six weeks. Let the young plant grow to six inches, then cut it back to three inches to encourage stronger root growth. When the new leaves have emerged again, plant the avocado in a pot with soil (thanks to the California Avocado Commission for these instructions).
Repot your avocado every spring, when the plant begins to grow again. For the first few years, trimming your avocado is necessary to encourage a bushy plant. The first serious trimming should occur when the plant is only 12 inches tall. At that time, cut it back to 6 inches and allow for new leaves and stems to form. As it gets taller, pinch off new growth throughout the summer to force new branches to form.
Avocado fruit from new growth.
Although there are about 1,000 varieties of avocado, the one most likely to find its way into your home is the Haas avocado, which is grown in tremendous quantities in California and throughout Latin America. These are small, pebbly avocados with a high fat content and delicious flesh. Larger, lighter green Florida avocados are also found in season. These have less fat and are sometimes marketed as health-conscious avocados.
Avocados grown indoors are mostly novelty plants. If you want it to fruit and turn into the tree it really is, you'll have to move your avocado outside (and perhaps move yourself to a warmer climate). Still, to keep an indoor avocado healthy, give it plenty of light and water, and feed it regularly. Pinch off new growth and look for symptoms like leaf yellowing, which can indicate too much water or sluggish drainage.
Also look for white crust on the soil—this generally means an excess of salt build-up from the fertilizer. Flush the pot regularly.