Preparing the Soil
Getting the soil ready for planting an avocado tree is a key factor in its overall health and growth. Start by digging a hole with a width of 2 to 4 feet and a depth of 2 feet. Place this hole at least 15 feet away from other structures such as houses, play structures and fences. The soil should be well-drained loamy sandy soil, with an ideal pH between 6.0 and 7.0. If appropriate, fill the bottom of the hole with four to six inches of organic material like compost or potting soil to improve drainage and soil structure.
Planting the Tree
After carefully removing the avocado tree from its pot, carefully spread the roots and check for signs of visual damage. Position the tree so that the root collar, which is the point where the roots meet the trunk, is at ground level. The more the roots that are exposed, the more the tree will suffer, so the goal is to have them almost covered, but still visible. Then, fill up the first few inches of the hole with soil mixed with compost and fertilizer. To help the tree establish healthy roots quickly, add fertilizer with low amounts of nitrogen and other nutrients. Finally, water the newly planted seedling and make sure that the soil is evenly moist.
Fertilizer and Mulch
Fertilize the avocado tree every four to six weeks in the spring and summer with a fertilizer that’s made specifically for avocado trees or a general-purpose 10-10-10 fertilizer. In the winter, reduce the amount of nitrogen used so the tree doesn’t suffer from cold temperatures. Additionally, add a thin layer of mulch, such as fine bark or straw, to the tree’s root system to help protect its feeder roots from the sun’s strong rays during the summer months. Keep the mulch two to four inches away from the trunk at all times.
Pruning and Watering
It’s important for the health of an avocado tree to prune the excess branches that are more than a year old. This encourages better light flow and air penetration through the tree’s canopy. While the tree is still young, it may require weekly watering; however, mature trees don’t need as much water. When watering, make sure the soil is evenly moist and avoid overwatering to prevent root rot.
Diseases and Pests
Just like any other tree, avocado trees can experience various diseases and pest infestations. Common enough avocado tree diseases are Phytophthora root rot, root rot and gummosis. To prevent disease, try to avoid overwatering and ensure the soil is well-draining. To prevent animal infestations and damage, such as those caused by rodents and birds, deterrents like plastic owls or netting can be used.
Feeding the Avocado Tree
Avocados are heavy feeders and will appreciate several different nutrient inputs during their growing season. Applying a high-potassium fertilizer that contains a little bit of nitrogen, such as 8-3-9, 6-6-6 or 10-10-10, twice per month from spring to late summer is recommended. In the winter months, applying a fertilizer with even less nitrogen, such as 0-12-4, is ideal.
Harvesting and Storage
The time to harvest an avocado depends on the variety being grown. A handy rule of thumb to remember is that early season varieties are ready to harvest when they’re hard and dark green, while late-season varieties will only be ready to harvest when they’re soft and yellow-green. Avocados can be stored either ripe or unripe in the fridge to slow down ripening and should never be stored in the freezer.
Best Practices for Staking and Grafting
To ensure that an avocado tree produces fruit, it should be both staked and grafted. Staking, or pruning the tree so it takes a certain shape, will help keep the avocado tree in place while it grows and helps create a structure that allows more light to reach the top of the tree. Grafting, or joining two or more trees together, is another way to ensure a larger harvest and growing variety.
Soil Maintenance
Maintaining soil health is key to producing a healthy avocado tree. Test the soil regularly and look for pH levels between 6.0 and 7.0. If levels are too low, add dolomitic lime or sulfur to bring them back in line. Adding compost annually to the soil, such as green manure, will help keep the ground productive and disease-free.
Irrigation System
Irrigation systems can help keep avocado trees healthy and productive during the hot summer months. Install a drip irrigation system with soaker hoses that water the plants more regularly and accurately. Avoid using an overhead system because it can cause leaf spots and other diseases. During the winter months, reduce the amount of water being provided to the tree to prevent root rot.
Supplements and Fungicides
Due to their heavy nutrient demands, avocado trees may require additional supplements to stay healthy. Sul-po-mag, a magnesium sulfate supplement, can be used to prevent blossom-end rot and ensure stronger foliage growth in the spring and summer months. Fungicides can also help treat fungal diseases such as scab or powdery mildew. Make sure to follow the instructions provided by the fungicide’s manufacturer when applying.
Sun and Shade Management
Avocados prefer a lot of sunlight and a location that gets six to eight hours of full sun per day. While best practice is to keep avocado trees out of the shade, avocados can also handle a moderate amount of shade for longer periods of time throughout the year. If an avocado tree becomes too shaded during the summer months, it’s important to shade it for only a few hours a day until the leaves become used to the change in light.
