Frequently Asked Questions

Using a trowel or shovel, dig a V-shaped hole in the soil four to six inches deep. Remove the entire soil wedge. Collect similar “wedges” from several spots in the area you wish to plant. Mix all the individual “wedges” together. One pint of this mixed sample is sufficient for testing purposes. The sample should be free of all plant debris and rocks. It is also very important for the soil to be completely dry.

Alkaline soils are a result of natural soil characteristics or excessive applications of lime. The pH of over-limed soils can be lowered by adding sulfur, iron sulfate, aluminum sulfate, or ammonium sulfate. Naturally alkaline or calcareous soils are common in coastal counties. It is difficult, if not impossible to lower the pH of these soils. Nutrient deficiencies in plants growing on calcareous soils should be treated by nutrient foliar sprays.

Dolomite is a type of lime: There are various forms of lime used to increase soil pH. Standard lime contains calcium. Dolomitic lime contains calcium and magnesium. Whenever lime is recommended, dolomite is suggested since it will adjust the soil pH and also add magnesium which is usually deficient in Florida’s sandy soil.

Lime is added to soil when a soil test determines that the soil pH is too acid. Lime reacts with water and releases calcium which neutralizes the acidity of the soil, thus raising the pH of the soil.

Optimum pH will vary from plant to plant, but a pH between 5.0 7.0 is generally accepted as the best range for most plants. The pH of the soil governs what nutrients are available to plants. If the soil pH is above or below the recommended range (5.5 – 7.0), nutrients may not be soluble (absorbable by plants) or they may be so soluble that they become phytotoxic. Therefore, a plant can show signs of nutrient deficiencies or toxicity even when the correct amount of fertilizer is applied to that plant.

pH is a measure of soil acidity (sourness) or soil alkalinity (sweetness). pH is expressed by a number on a scale from 014. A neutral reading is 7. Any reading below 7 represents an acid soil and the lower the number the more acidic the soil. Any number above 7 indicates an alkaline condition and alkalinity increases as the number on the scale increases.

Pick up a handful of moist garden soil and squeeze it. If it sticks together like cookie dough it is probably clay. If it doesn’t hold together in a ball and it feels gritty, it is probably sandy soil. If it holds together in a ball but crumbles if tapped lightly it is loamy soil. Or you can bring a sample to the local Master Gardeners’ Office.

When the term “organic” is used on a fertilize label, it means that all or part of the nitrogen is in an organic form. This form must be identified as synthetic-organic and/or natural-organic, and the respective percentage or each must be specified (for example: 70% synthetic, 30% natural). Synthetic organics are organic compounds which are chemically synthesized such as Urea Nitrogen. Synthetic organic nitrogen is identified in the guaranteed analysis as Water Soluble organic nitrogen and/or Urea Nitrogen. Natural organic nitrogen comes from natural sources such as manure, seed meal, sludge, dried blood, etc. The percent of natural organic material is listed under Water Insoluble Nitrogen. Recently, many forms of water insoluble nitrogen have been developed (sulfur-coated urea, ureaformaldehyde, Isobutylidine dilurea-IBDU, etc.). These sources act like natural forms in that the nitrogen is slowly released.

Plants need about 1″ of water per week during the growing season. This can come from rainfall, irrigation or a combination of the two. This can be achieved by leaving a sprinkler on the plants for approximately one (1) hour. To check, bury a can at soil level and measure the amount in the cup after one hour. Then adjust time accordingly.

Mulching is considered a beneficial practice for all ornamental plants. Mulching conserves soil moisture insulates the soil (keeps it cooler in summer and warmer in winter) and suppresses weeds. Organic mulches such as shredded wood, pine needles or oak leaves are preferred to inorganic mulches such as pebbles and stone. The desired depth of the mulch is 2″ 3″ after settling. The area immediately around the stem of the plant should be left free of mulch.