Where to Plant an Avocado Tree
Grow your avocado seedling indoors from the big brown seed from the center of the fruit. You can grow the tree outside if you live in one of the warmest parts of the U.S. Although they grow in plant hardiness zones 8-11, in the U.S., avocados only thrive in southern parts of Florida or California, and in Hawaii. Avocado trees are subtropical plants native to southern Mexico. If you live in a region where winter temperatures regularly drop below freezing, plant the avocado tree in a container so you can move it indoors for winter. Indoor avocado trees should be grown in potting soil, not garden soil, to allow air and water to circulate freely.
How and When to Plant an Avocado Tree
It’s easy to sprout an avocado seed, as you may have learned in childhood. Buy an avocado, enjoy the luscious green flesh, then wash the seed. Remember which end of the seed was on top and which was on the bottom. Then, poke several toothpicks into the equator of the seed and rest the toothpicks on a glass of water so that the bottom inch of the seed is in the water. Plant at any time of year, as the seedling will remain indoors at this point. Place the glass somewhere warm but out of direct sunlight, adding water as needed to keep the bottom inch of the seed in the water. Roots develop first, followed by the emergence of a seedling. When the seedling reaches 6 or 7 inches tall, cut the stem in half, or about 3 inches tall, to encourage the plant to put its energies into new growth. When the seedling has several leaves and thick roots, plant the seed in potting soil in a 10-inch-wide pot that has drainage holes.
Avocado Care Tips
Light
Place the pot in a sunny window indoors or move it outside whenever the temperature is 45°F or warmer. Keep young potted avocado trees in partial shade; the leaves can sunburn if they get too much direct sun while they’re still getting established.
Soil and Water
If the tree grows indoors in a container, plant it in potting soil and water weekly. If the container is moved outside in warm, dry weather, water more frequently . If you are planting it outdoors, choose well-draining garden soil and water the newly planted avocado tree every 5 to 10 days with several gallons of water. It’s better to water deeply less often to force the roots to grow to reach the water. Keeping about 6 inches away from the tree trunk, mulch with about 3 to 6 inches of coarse bark or cocoa bean hulls to retain moisture.
Temperature and Humidity
If you live in a warm enough hardiness zone, you can plant outdoors. Avocados perform best in temperatures between 60°F to 85°F in areas with medium or high humidity.
Fertilizer
In summer, fertilize weekly with a fertilizer with nitrogen, indicated by a higher first number, such as 7-4-2. Avocados also need a small amount of zinc, so look for a fertilizer with that component. Avoid fertilizing during the winter when growth is minimal.
Pruning
Prune the tree regularly. Every time it grows another 6 inches tall, cut back the top two sets of leaves. When the plant reaches 12 inches, cut it back to 6 inches. When it reaches 18 inches, cut it back to 12 inches, and so forth. This encourages bushier growth.
Repotting Avocado
If you grow the avocado tree in a container, gently remove it as it grows and place it in successively larger pots, going up in diameter 2 inches at a time.
Pests and Problems
When they are grown outdoors, avocado trees are susceptible to damage from caterpillars, mites, thrips, borers, and other beasties, all of which can be handled by the observant grower. The University of California Integrated Pest Management offers a guide to identifying and treating these pests on avocado trees.