Get back to soil care basics

by Kathy Warner
Nassau County Master Gardener

Special/Nassau County Extension -- My Nassau Sun Logo

Got your glove and shovel handy? About to buy some plants at the nursery? Ready to dig in for the fall growing season in North Florida? Stop! Wait. Not just yet. It starts with soil.

Some characteristics of soil are relatively fixed, and gardeners must work around or with them. Soil texture, or the proportions of different mineral particles of varying size, is one of these. Sand particles are the largest, clay particles are the smallest, with silt in between the two.

Sandy soils have a coarse texture, drain quickly, and tend to be low in nutrients. Clay soils are fine-textured, drain slowly, and usually are more fertile than sandy soils. Silty soils are intermediate in texture, drainage and fertility. Soils that have characteristics of all three are called loams.

Successful gardening lies in what you do before plants go into the ground. Start with a test. The University of Florida Extension Soil Testing Laboratory will perform a standard soil fertility test which determines pH, lime requirement, phosphorus, potassium, calcium, and magnesium for a fee of $7.

To learn more about your soil, dig a few small holes and evaluate the soil's texture, structure, and biology. A nice earthy smell indicates that microorganisms are hard at work breaking down organic matter. The presence of earthworms and millipedes indicates a healthy ecosystem. Roots should look white and healthy. Brown roots indicate that the soil is waterlogged and that the roots are not getting enough oxygen. If roots stop growing at a certain point, you may have a compaction problem. Another clue to compacted soil is the tendency for rainwater to pond or run off the soil. Correctly structured soil absorbs rainwater fairly rapidly.

The wrong balance of nutrients can be detrimental to plant health and have an impact on taste and nutritional quality of vegetables. For example, a nitrogen deficiency can stunt plant growth and reduce yields. Too much nitrogen encourages fast foliage growth which could attract aphids and be susceptible to disease. Too much magnesium can lock up potassium.

Fertilizers provide a quick, high dose of nutrients. But they offer no organic matter to the soil. Organic amendments add nutrients, help condition the soil, and provide important food for microorganisms.

You can add organic matter and minerals to your garden in several ways:

- Composting with "waste" materials such as fallen leaves and green plant debris.

- Mulching both flower and vegetable gardens with grass clippings or other materials which gradually decompose adds organic matter and encourages earthworms.

- Cover crops aid vegetable gardens by loosening compacted soils, adding organic matter and fixing nitrogen into the soil for other crops.

- Purchased mineral amendments such as green sand, rock phosphate, and gypsum added in the fall to be ready for spring planting

- Plant or animal-based amendments, such as blood or bone meal, manure, fish meal and kelp.

- Liquid fertilizers, including compost tea, fish emulsion and kelp, provide a quick shot of nutrients to the plants through their leaves. Apply early in the morning when leaf pores are open.

Amend your soil as your soil fertility test results recommend. Your garden will grow and your plants will thank you for it!




Master Gardener volunteers are trained by County Horticultural Extension agents and are required to serve 75 volunteer hours in year one of their accreditation and 50 volunteer hours annually in all subsequent years to maintain their certification.

Nassau County master gardeners serve under the direction of Rebecca L. Jordi, UF/IFAS Nassau County Horticultural Extension Agent. For information on the master gardener program and application requirements, contact Jordi at 548-1116 or



Kathy Warner

Kathy Warner is an Amelia Island resident and an active master gardener volunteer with the Nassau County Extension Service and the University of Florida/IFAS.