We are offered many opportunities to learn as part of the volunteer program at FTBG. Yesterday I went to the titled class given by Richard Campbell and thought I'd share my notes with the forum. I learned a lot. I had a work conflict a couple weeks ago and missed the Fairchild farm field trip. The notes are as written and not organized in any particular order.
I hope members find them as useful as I did.
The most important thing to keep in mind is that all fertilizers are salt and can kill trees. Be conservative on the side of less.
Modern fertilizers will not make you a better grower. They are recent developments of the petroleum industry. Before the 1940’s there were no fertilizers and we were better horticulturists.
Pruning and fertilizes should be done yourself and not tasked away to 3rd parties.
Don’t store fertilizer near gas.
Slow release fertilizer is good and helps you with a conservative application.
Fertilize a day before there is a 60% chance of rain in forecast. Don’t do prior to a forecast heavy rainfall. 6 inches of rain will wash away all fertilizer before absorption. Worse, it ends up in the ocean and causes algae blooms.
Organic sources are hard to find. Chicken manure is good, but needs 6 months to compost. Be careful with horse manure as it can have needles and be contaminated with fly pesticide. Its high in boron/molybedenum. Needs to compost at least 6 months.
Kitchen compost is excellent, but will not be available in sufficient quantities to be effective on any scale.
Dead leaves have little nitrogen as it’s been pulled out by the tree prior to leaf dropping. Straight mulch is a good fertilizer.
About fish as fertilizer, he said that if you bury a dead fish in a hole while planting a tree, the tree will die. Too much ammonia.
Slow release fertilizer is good and 10x more expensive. There are different release times, up to 12 months. FTBG uses 12 months to save on labor. They use 8/4/11 Harrell’s. When rainy season ends they add a 3 month application.
Soil temperature is key when applying fertilizer. Less than 65-70 degrees means the tree will be dormant regardless of air temperature.
It’s better to use low analysis with more frequent applications, never higher than 11% nitrogen.
Organic sources will have almost no “K”.
For fruit 8/3/9 + minors is good. In South Florida, the micro nutrients are the most important. High PH soils render micronutrients unavailable. They remain in the soil tied up by organic elements. Micros must be applied via a chelate (expensive), the most expensive part of fertilization. Southern Ag foliar is good but not as good as using a chelate. Foliar gets the job done to a point, but there is better absorption via the roots.
Iron is important for broadleafs. For Palms manganese/zinc are most important.
When applying chelates, it’s hard to overapply in S. Florida. Applying is useless when soil is cold.
Make sure to apply fertilizers to dripline area for maximum absorption, not near trunk.
The amount of fertilizer to apply depends on how much fruit you take away. Fertilize heavy if you fruit heavy.
Mangos are an exception, they will not bloom if “fat and happy” being fed a lot of fertilizer. More fertilizer = less fruit. Starve them to get fruit. “K” is important for flower production. 0/0/51 for mangos. Will not hurt tree. It gives mangoes better color, higher sugar, and firmer fruit. N will negatively impact fruit taste. Do not apply muriate of potash to mangoes. It is full of chlorine. Urea will kill a mango tree.
With avocados and jackfruit, it doesn’t matter. The more you fertilize, the more they grow and fruit.
N makes leaves green. P – lots of phosphorus in ground in S Fla. We don’t need it in the fertilizer. Lotus is being planted to remove P and heavy metals/pollutants in areas of S Fla.
Cheap fertilizers should be avoided, they have high chlorine content.
Minors key for lychee/longan, not as much for mango. It’s expensive and hard to apply.
General purpose – there is no slow release 6/6/6.
Palms should be high in “K” (8/2/12, 11/4/11, 9/4/12). Keys are micronutrients
Fruits (8/3/9) good general purpose fertilizer. Harrell’s slow release is good.
Pruning – Ran short of time for this topic as most of the 2 hours were consumed by the fertilizing discussion.
No right or wrong way to prune. Prune for fruit production and hurricane protection. The bigger they are the harder they fall. Don’t let anyone else do your pruning. Start early and prune the entire life of the tree. A multiple hurricane year will make you glad you controlled size.
Palms – easy…only remove dead fronds.
Broadleaf – prune for aesthetics, size, shaping, effect.
Suggestions – take arborist classes, read books on arborist techniques. Find old books as there is nothing new on the subject that wasn’t known a long time ago.
Tools – loppers, handsaw, clippers, machete. Handsaw preferred over chainsaw as this gives you discipline on cuts.
Objectives for fruit tree are to produce fruit and keep small. Mango trees, use clippers, make into bushes.
If a tree falls over, it will never be a permanent tree again. It will never develop a root system to support a top.
From a 13 foot tree to a 15 foot tree, there is a 30% higher chance of it blowing over.
Topic: Richard Campbell Pruning and Fertilization Horticulture Class for Fairchild Volu (Read 3905 times)