If you’ve grown an avocado tree from a pit and have planted it as a houseplant, you may be wondering how to get it to grow big and healthy. The tree pictured below was originally planted from an avocado seed about five years ago.
At the time in 2014, I did a video about how to plant an avocado tree grown from a pit in water. And then I did an update video two months later of the avocado seedling after the planting.
The tree, who I named Sam, has had some time to grow since then, and this is the result. There’s a new video about the avocado tree, now more than four years later. Avocado trees are definitely among the category of different plants, when it comes to growing them indoors.
With that background out of the way, let’s talk about how to grow an avocado tree as indoor plants successfully.
Here are the important points to consider when growing fruit trees indoors—in particular an avocado plant.
Lighting for Indoor Grown Avocado Trees
Adequate lighting is critical to successfully growing indoor avocado trees. It’s vital that the trees have bright light, and enough of it. Unless you have a home with large windows with an eastern or southern exposure and live in a climate that gets a good amount of sun, it’s going to be difficult to grow avocado trees on a windowsill and provide enough light without using supplemental artificial lighting.
The best supplemental light for avocado trees indoors is full-spectrum lighting. This type of lighting simulates sunlight. They grow outdoors in full sun, so this is ideal. These light bulbs are fairly easy to get nowadays and can be put in any type of lighting fixture. They come in bulbs and tubes. Place the avocado tree as close to the light as possible—although not closer than 3 to 4 inches. Preferably the light should be shining down on the avocado tree.
If you have an AeroGarden, these have a great lighting system for avocado trees. Provide avocado trees with about 12-16 hours of lighting per day.
Watering Indoor Avocado Trees
Avocado trees drink quite a bit. That means that you don’t want them to dry out but you want the soil moist. However, be careful to not overwater, as they are susceptible to root rot. Your best bet is to water when the top one to two inches of soil has dried out. (One inch for small trees and two inches for larger trees).
When you water, soak the plant well until the soil is quite moist. If you watered over a drainage tray, make sure that the bottom of the pot doesn’t sit in water after you’re done watering. Bring smaller plants to the sink and soak well.
Always use warm water when you irrigate avocado trees indoors. This is actually the case with all houseplants, but avocado trees are a semi-tropical plant and are used to growing in warm, humid temperatures.
Fertilize Avocado Trees Regularly
Avocado trees require regular feeding. Use a well-balanced, organic fertilizer that contains nutrients like alfalfa meal, which is a natural growth hormone, bone meal, which contains phosphorus for healthy roots and flowering and worm compost, which has a lot of trace nutrients that avocado trees require.
Kelp meal and guano are other good sources of nitrogen and trace elements. Mycorrhizae are another good addition. As long as it’s organic, an avocado/fruiting tree fertilizer also works well.
Fertilize indoor grown avocado trees in early spring, the middle of summer and early fall. Avoid fertilizing in winter months. If you’re using granular fertilizer, use a wooden skewer to make holes in the soil 3-4 inches deep and sprinkle the fertilizer in the holes. Cover with soil and water after you’ve fertilized.
Potting Avocado Trees Up Indoors
Plant avocado trees in a well-draining, yet rich potting mix. When grown as indoor houseplants, avocado trees require something that will not stay too moist indoors, as that can lead to root rot. Plant in a pot that is no more than one pot size larger. The proper plant /pot ratio is one-third pot to two-thirds plant.
Trim Avocado Houseplants Occasionally
If you want an avocado tree to grow big and healthy in your home, avoid pruning it back by more than 10 percent. What you want to do is just prune out any crossing or dying branches. If a stem is growing in a manner you don’t like, tie it closer to the trunk or stake it to train it to grow where you want.
Over-pruning avocado trees will lead to a slow-down in growth, and if the tree is over-pruned too much, you could lose the tree.
Pollination for Indoor Avocado Fruit
If you get flowers on your indoor growing avocado tree, rejoice that it’s blooming! Then hand-pollinate so you get some cross pollination. Once the flowers open, use a child’s paintbrush with a thin point and put the tip of the brush in a flower. Jiggle the brush a bit when hand pollinating and then go to another flower and do the same. This will mix up the pollen between male and female flowers and may result in fruit.
Keep in mind that avocado tree flowering and fruiting indoors is rare, but it can happen. The plant will need the ideal growing conditions mentioned here to do so, though.
Provide Air Circulation for Avocado Trees Indoors
Avocado trees like to feel like they’re outside. Open nearby windows for a breeze and air movement, or run a fan periodically. Doing this will also cause young avocado trees to develop strong trunks.
Watch out for Pests on Indoor Avocado Trees
When growing plants indoors, keep an eye out for mealybugs and spider mites. Spray mealybugs with isopropyl alcohol every three days, until you get the invasion control. After the bugs die from spraying, wipe them off.
Spider mites are an indication that your avocado tree is too dry. Mist with water regularly to bring up the humidity level. Rinse the leaves regularly. If possible, give the tree a shower once a week until the spider mites are under control. You can put the plant in the shower.
Indoor gardening is an adventure when you grow an avocado tree. Good luck!