Once you have unpacked the tree, be sure to remove the plastic bag that keeps the soil in place for shipping and follow the next step of acclimation.
All avocado trees need to be protected from heavy frosts and strong winds. They prefer to be planted in sunny locations with well-drained soil. Most avocado trees can reach a height of 25'+ feet when fully grown, though their size can be controlled with annual pruning in the spring. Selecting the proper location to plant your avocado tree is important for successful growth.
Type A or Type B Avocados:
Avocado varieties are identified as being either Type A or Type B. It is a common misconception that these types refer to male and female plant types that must be planted together for successful pollination. Type A and Type B refer to the life cycle of avocado flowers, which only behave normally under specific temperature ranges. All avocado flowers are both male and female at various points in their daily flowering, making it possible for avocado trees grown in areas with mild climates to be fruitful without the help of another tree acting as a pollinator.
Acclimating your greenhouse-grown avocado tree is vital to the success of the tree in its first season. It will shock the tree if you put it in direct sunlight for too long the first couple of weeks. The ideal location for the first couple of weeks outside is a spot by the house with indirect sunlight that gets an hour or two of direct light throughout the day. After the acclimation period, you can move your adjusted tree into its final location, which ideally gets 8 hours of full sun daily. The use of tree paints and foliar sprays like IV Organics is very helpful during this process to block reduce exposure to intense sunlight.
Avoid disturbing the roots at all when planting. Avocado trees thrive when planted in the ground with well-draining soil and full sun(8+hrs). Heavy clay soils are not ideal for avocados but building a mound above the native soil level with a well-draining mix of sand, compost, and fine mulch to get your tree up off the clay. This mound should be taller than your tree pot is deep and about 6' around. Once your ground is prepped you can dig a hole in your soil as deep as your tree pot and make sure to plant no deeper than the soil level of the tree. Avoid pilling up any soil against the trunk as this can encourage rot and fungal activity. If you live in a climate that regularly drops below 32°F you will need to provide frost protection during winter or grow indoors as the cold will severely damage your tree.
When growing in a container, you need to provide a lot of space for the roots to spread out. A common variety grown in pots is the Little Cado, which is a small avocado fruit variety with very low vigor. Avocados need at least a 40-gallon container for their spreading root systems and expect your tree to reach about 10-12 feet at maturity. This should be done over time starting with a smaller container and working your way up. Much like outdoor growing, you want to provide a warm location with 8+ hours of sun a day and plant in a well-draining soil mix.
Avoid overwatering or keeping the roots too wet, as they are susceptible to root rot. Avocado trees prefer less frequent, deep watering to frequent, shallow sprinklings. Creating a watering basin around the drip line of the tree can aid in deep watering. As the tree grows, be sure to expand the basin as needed to keep it as wide as the spread of the branches. Deeper watering promotes deeper root growth and strengthens your tree. Generally, once-a-week watering works well for in-ground or container plantings. Be sure to adjust based on weather conditions. Are you noticing a lot of dieback or browning of your leaf tips? This damage is typically caused by salts in your water. Avoid using water from your water softener to water your trees if you have one to minimize the damage. In most cases, the damage done is purely aesthetic and the tree will continue to photosynthesize using the remaining leaf.
Mulching & Fertilizing:
Providing a thick layer of mulch is a good way to help your tree retain moisture, improve soil quality, and keep the roots protected during the cold months. Apply a 3 to 4-inch layer of mulch in spring and fall under the canopy of the tree, keeping at least 6 inches away from the trunk of the tree to prevent stem/trunk rot. This is also an ideal time to fertilize with a balanced avocado/citrus fertilizer like our Romeo Plant food (follow manufacture - provided instructions). Good organic plant foods include composted manure, blood meal, fish emulsion, alfalfa meal, or vermicompost. This is another step where you want to avoid disturbing the surrounding roots.
Keep pruning to a minimum to shape and control size. Frequent pinching of terminal buds on young trees is a good method to shape the tree, rather than heavy pruning. You do not want to expose too much of the trunk to the sun as avocados are susceptible to sunburn. If you do see that you aren't getting enough leaf coverage on the trunk it is common practice to paint your tree with tree paint or IV Organics Plant Guard to protect it from sunburn.
Summer & Winter Weather Advisory:
During the summer, you must protect your trees from intense sun and any temperatures more than 90°F with either shade cloth suspended above the tree and/or Plant Guard tree paint / foliar spray.
Similarly in the winter, you will need to protect your trees from any temperatures below 32°F. A couple of hours of exposure is fine but extended periods below freezing will cause significant dieback and some cases total loss of the tree.
These steps are particularly important for young trees as they have less structure and vigor than more established trees which can handle a bit of dieback from frost or sunburn.