Planting 400 Hass Avocado Trees: Expanding Our Commercial Mountain Grove
We are planting 400 two-year-old Hass avocado trees across the lower five acres of our 10-acre commercial grove on the mountain north of the house. Planted carefully and watered right, grafted trees like these mostly bear their first crop in the third year after planting and reach full production in years eight to ten.
Today marks one of the biggest days of the season on our farm. Our home grove holds about 30 trees on just under an acre, so planting several hundred nursery trees on a mountain takes steady planning and a lot of hands.
From the home grove to the mountain acreage
Caring for 30 trees around the house gives us a close look at each tree’s health, soil and watering needs. Ten commercial acres demand systems that scale.
Our mountain grove sits high with views across the valley, and good airflow helps on cold winter mornings. Cold air drains downhill, and Avocado Production in California: A Cultural Handbook for Growers, Book One advises planting above the frost line for exactly that reason, since Hass freezes below 29 to 30°F. The lower five acres have been prepped for this delivery so the young trees can go straight into the ground.
Read nextBehind the Scenes: Documenting Daily Life in a California Commercial Avocado Grove
Why we chose two-year-old Hass trees
Choosing nursery stock is one of the most important decisions in starting a grove. We brought in 400 two-year-old Hass trees for a few reasons:
- Size and sturdiness: Older nursery trees go into the field with more growth behind them than small starts.
- The variety that sells: The handbook calls Hass the variety of best overall quality, with the longest harvest season, and the recommended choice for new plantings.
- A faster start: Grafted trees mostly bear in their third year after planting, so a bigger tree gets the clock running sooner.
How do you plant an avocado tree so it survives?
The handbook is blunt that over- and under-watering are probably the most common reasons trees fail at planting. Clonal rootstock trees have weak root systems and their root balls break easily, so how each tree is handled matters as much as where it goes. The steps we are following this week:
- Layout: Marking tree spots across the hillside rows for sunlight and equipment access.
- Holes: Digging holes about the same depth as the root ball. A deeper, backfilled hole lets the tree settle and can sink the graft union below the soil line.
- Handling: Never lifting a tree by its trunk, because it can snap at the graft. One tree at a time, with a hand under the root ball.
- Setting the tree: Keeping the top of the root ball slightly above the soil and uncovered so it takes water, then tamping in native soil and leaving a slight basin.
- Water right away: Filling the basin as soon as the tree is in, and never letting the root ball dry out.
How much water does a newly planted avocado tree need?
Less than a mature tree, but more often. The handbook’s guide for young trees is 5 to 10 gallons a week, split into two or three irrigations, delivered close to the trunk. Young trees set on a mature grove’s once-a-week schedule get alternately drowned and dried.
Timing matters too. Spring is the best time to plant, because avocado roots usually flush in May. Trees planted in summer need water every two to three days, without letting the soil stay soggy.
Protecting young trees in the first year
The handbook recommends a thermal wrap on the trunk against summer sunburn, removed after the first year, and several inches of straw or wood-chip mulch, with no manure because of the salt. Weeds are controlled by mulch and hand weeding, with no herbicides in the first year. That matters to us beyond the young trees, because weeds harbor persea mites.
How far apart are avocado trees planted?
Four hundred trees on five acres works out to about 80 trees an acre, inside the 50 to 100 trees an acre that the handbook’s variety table lists for Hass. For comparison, the traditional California spacing was 20 by 20 feet, or 109 trees an acre, a figure the handbook says was probably influenced by 20-foot lengths of PVC pipe. Some growers planted closer, at 15 by 20 feet, planning to remove every other tree when the canopies met. Many never did, and those crowded groves ended up fruiting only at the top.
Slope adds its own rules. Avocados grow well on hillsides, but harvest gets harder, and the handbook notes that steep groves need a topping and pruning program to keep the fruit within reach.
Follow our grove expansion
Expanding a grove on steep mountain ground comes with hard labor, practical problems and big rewards. We will be documenting every stage on camera, from digging holes and running drip lines to staking and shading these young trees. Follow our field updates to watch this hillside turn into a working grove.
We are planting these new trees with everything we learned bringing the old grove back, and the full picture is in our guide to growing avocado trees. The first chapter of that work, the well, the power and the first replant, is in our grove revitalization notes.
