I have 120 citrus in ground and 5 potted, 6 mango in ground, 3 lychee and 20 avocado in ground with an average age in ground of 2 years. I live in Miami. My trees are immaculately perfect. Trees range in size from 3.5 ft to 15 ft.
For 2 years I struggled with fertilizers and micronutrients as each new disappointment arrived. eg yellow leaves, leaves with yellow veins and the reverse, defoliations, burnt tips or leaves etc, etc, etc.
To make a long story short, the combination of 9-3-6 Foilage Pro without vinegar and Soar micronutrient sprays combined with Orocit agricultural oil to act as a spreader sticker and insect suffocater helped more then anything to get citrus perfection. If you are buying the FP I recommend greenhousemegastore as they sell a gallon for $40 the lowest price on the web. I called Dynagro to buy five 5 gallon containers and they wanted $250 each plus $157 postage for all 5. But a local company got it for me for $150 per 5 gallon container so you can figure what I now think about the manufacturer Dyna gro. Also, I experimented recently with vinegar to lower my ph because my watering water has a ph of 8.4 and I ended up causing some crazy burned spots in the center of some leaves so since I've had perfection without the vinegar I'm not going to use it again.
A technique I have used since the beginning is that I surround my tree trunks with a round wall about 24 to 36 inches in diameter so that when I pour my water mixed with FP it does not spread out but goes straight down. Home depot has plastic edging that can be attached to each other and then stuck in the ground in a closed circle so the water and FP goes where you want it to go. I use 3 ozs of FP in 5 gallons of water and use 2.5 gallons on the smaller trees and 5 gallons on the larger trees. If it's the dry season I'll do this 1 X/ month. Rainy season 2 X/ month. Rain washes the nutrients out. And I spray every 3 weeks. Every leaf on every tree is perfect. This is the Home Depot edging I use:
Home Gardener Borderline II 2 ft. Plastic Edging
Model # 21005
Store SKU # 268035
No other fertilization is necessary. 9 of my citrus get very little light and with this technique they are thriving too. These trees are on my 1/2 acre lot along with my house so they are pretty close together.
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Fert instr
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