Those citrus trees need room to breathe

We have an orchard. Not just a lemon or an orange here and there, an orchard of about 50 trees.

When we arrived in 2012, the previous owner had planted about 25 trees in soil 6 inches deep and underlain by clay. And they were three feet apart. She planted lemon trees a foot from the path down the hill. Lemon trees torleyheader020816have thorns. How did she think she was going to be able to walk down the path?

Then she had a pond dug. A 30- by 50-foot pond (more than 9×15 meters). The man with the backhoe cautioned: “Ma’am, it’s the wrong kind of dirt. It won’t hold water” (The clay was uphill under the
citrus trees). “There’s not enough water flow, it will be stagnant and breed mosquitoes.” How do I know? He is the same man who filled the pond in with dirt, because it didn’t hold water, the little water that accumulated was stagnant, and bred mosquitoes. He laughed the whole time.

Needless to say, I now have a 30- by 50-foot orchard. The soil drains very well. And those stunted clay-dwelling trees? They now have room to grow.

Standard-sized trees require 12 to 25 feet between trunks while dwarfs need only 6 to 10 feet. It does vary: Standard orange 20 feet, standard grapefruit, 25 feet. Plant them any closer and you lose fruit production due to mutual shading which decreases photosynthesis. Close planting also causes the roots to entangle and compete for scarce nutrients. Nutrient competition and depletion causes yellowing and wilting of leaves and lowered fruit production.

If you have closely planted fruit trees, as we did when we arrived, they should be transplanted before the roots entangle, which depends on how close they are. Some of ours were 2 years old and well entangled. They have not done as well after transplanting. Others, further apart, are doing very well. We are fortunate that the pond was downhill out of the wind, in full sun and deep soil as citrus love a sunny windless environment. Here’s what we didn’t know.

Citrus, especially in conditions where there is a lot of rain, take more fertilizing that we realized. From February to October, a mature tree (over 5 years old) takes one pound of fertilizer  for every year of life! That is a lot of fertilizer. We use a 10-10-10 pelleted fertilizer on those mature trees every three months in that growing season. That’s 180 pounds x 3 or 540 pounds. And that’s just for the grouped trees. We have others scattered around the property that are bigger and older. call it 1,000 pounds of fertilizer a year. Wow.

Here is the formula if you are just starting your trees. Time period is February through October: first-year trees, ½ pound every 6 weeks. Second-year trees, 1 pound every 7 weeks. Third-year trees,  2 pounds every 9 weeks. Fourth-year trees,  3 pounds every 12 weeks.

At year 5, trees are considered mature and need 5 pounds of fertilizer per tree 3 times in the growing season. After that, add 1 pound per year of age of tree (10 year old tree gets 10 pounds). And how do you apply all this fertilizer?  Fertilize from the edge of the canopy (the “drip line”) not at the trunk since the feeder roots are found there. Fertilize in a band as wide as the age of the tree: a 5-year old tree gets a band 5 feet wide.

I am still struggling with 1,000 pounds of pelleted fertilizer. Maybe I could just get my oranges in the store? Nah.

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