Tag Archives: fertilizer

Getting Green and Finally Creeping

Posted on by rhondacarrier

Asiatic Jasmine In a previous post, Needed Nutrients, I predicted that the soil test for my yard would indicate it was low in potassium. That is not unusual for southern Florida soils, but I was basing my prediction on symptoms of the Asiatic jasmine in my yard. I fertilized the plants when I realized they weren’t looking healthy, and waited to see what would happen.

The soil test results indicate that the soil is low in potassium, confirming my suspicions. Since I added the fertilizer, the leaves are almost all a healthy green color again. Even bigger news is that the plants are starting to send out runners. I was told that they sleep the first year after planting, the second they creep and the third they leap. They are finally creeping.

Are they green and creeping because of the fertilizer, because the weather is warmer, or because they are more firmly rooted than they were a few months ago? Probably, it is a combination of all three factors. I’m just happy to have a yard full of plants that are a healthy green color and are creeping across the empty spaces between the plants. Hurray!

What’s in Your Dirt?

Posted on by rhondacarrier

Soil Test Results

I debated about whether to test the soil in my yard. The Your Florida Landscape book says, “if you plan on simply using one of the commonly recommended fertilizers such as 12-4-8 or 16-4-8, there is no logical reason to go to the trouble of testing” (p. 104).

A common problem with urban soils, including the soil in my yard, is that the soil is brought in from somewhere to “fill” the yard and often isn’t fertile. I use a fertilizer, a 10-10-10 mix, but since I am putting in many new plants and trying to develop a Florida-Friendly landscape, I decided I wanted a better idea of the nutrient level in the soil. I followed the directions for taking a soil sample and sent it to UF/IFAS Analytical Services Lab (note: for Florida soils only). I have received the results already. The report says the soil is low in potassium but high in phosphorous and magnesium.*

What do the test results mean and what should I do? The numbers, 10-10-10 or 12-4-8, indicate the grade of nitrogen (N) to phosphorus (P) to potassium (K), so a 10-10-10 grade means N-P-K are in equal amounts. Since my soil is high in phosphorus, I am adding phosphorus when it is probably readily available in the soil, but I need to continue to add nitrogen and potassium since these are macronutrients needed by plants. I won’t throw away the fertilizer I have, but when I buy the next bag, I will look for a fertilizer grade with less or no phosphorus.

In an earlier post about Florida-Friendly Palms, I mentioned that palms are often deficient in magnesium (Mg) especially if they are only receiving lawn fertilizer which is commonly low in magnesium. The test results indicate that the soil is very high in magnesium, so when I put in palms I have information from the soil test to guide my purchase of fertilizer for the palms.

Was the test worth it? The information will help me to more wisely purchase fertilizer in the future. That makes me a better Florida-Friendly gardener and helps me to have a Florida-Friendly garden.

*(Note: There is no value for nitrogen which is needed by plants. The soil test report includes this note, “We do not test soil for N as there is no meaningful soil test  for predicting N availability.  Thus, the N recommendation was developed from research that measured response of the indicated crop to applied N fertilizer.  If you expect significant nutrient release from organic sources such as crop residues or organic amendments, estimate the amount mineralized and subtract that amount from the fertilizer recommendations given below to arrive at crop needs.”)

Needed Nutrients

Posted on by rhondacarrier

Asiatic JasminePlants require the following macronutrients in large amounts: nitrogen (N), phosphorous (P), potassium (K), calcium (Ca), magnesium (MG) and sulfur (S). The following micronutrients are essential also, but are needed in smaller quantities than the macronutrients: iron (Fe), manganese (Mn), zinc (Zn), copper (Cu), boron (B), molybdenum (Mo) and chlorine (Cl).

Observing plants may help to diagnose problems. A patchy, spotted coloration is probably a disease, not a nutrient deficiency. When looking at a plant with a pattern, the problem is probably a nutrient deficiency. Different deficiencies will result in different patterns which can be used to diagnose the problem. In the photo of Asiatic jasmine, the veins are clearly visible and the leaf tissue between the veins is no longer green but has turned a reddish-purple. Judging by the reddish-purple color on the older leaves, I would guess that when I receive the results of the soil test from my yard, it will indicate there is a potassium deficiency in the soil. Other symptoms to observe are whether the pattern is on the entire plant or on the older leaves or the younger leaves, or whether the stem is shortened, or the leaves are drying to brown.  The University of Florida will soon have a chart on their website to help diagnose plant problems using these symptoms and others.

If there is a nutrient deficiency, a fertilizer may be needed. It is important not to over-fertilize plants since excess fertilizer will run off into nearby ponds, rivers, etc. which reduces the water quality in those areas.

Important recommendations for use of and application of fertilizer is found on the University of Florida IFAS Extension website.