Soils in North Florida have a habit of being extremely sandy. Depending on your situation, this may be a good or bad habit – sandy soils tend to drain well, which can certainly help on a day when a tropical storm dumps 20 inches of rain on us. Those who want to grow plants, however, might consider it less of a boon.

Soil in general is composed of several things. First, the base of any soil are minerals, broken down over the centuries from whatever bedrock lies below. Mixed in with that is organic matter, which is mostly decaying plant material. In all the tiny spaces between the mineral and organic particles, air and water find their way in, and to top it all off, soil contains living things such as fungi, microorganisms, and invertebrates.

Sand is a soil type composed of relatively large particles. The smallest soil particles make up clay, and those that are sized somewhere between the two are termed silt. A soil most often has a mix of all three sizes of particle, meaning that a soil could be a sandy loam, a silty clay, or any other combination. Again, our North Florida soils tend to have ‘sand’ or ‘sandy’ somewhere in the description. If we choose to grow plants that are adapted to living in these soils, however, we can avoid many problems before they become issues at all.

Other things can make growing plants challenging, though. Soils can become compacted, fill soil is often brought in and mixed with strange materials, the water table in an area might be particularly high leading to dampness even where it should be well drained, and soil can become contaminated by chemicals or plant pathogens. What to do!?

For compacted soil, you can try aerating, which is a way of creating channels in the soil to allow water and air to penetrate to the lower layers. Tilling is an option, though if not done deeply enough can create a layer of hard soil beneath the surface which may retain water. Some plants can be grown to help break up tough soil, such as tillage radish.

Poorly drained soil can be dealt with by choosing plants that are adapted to dealing with wet conditions. Shrubs like wax myrtle or yaupon holly will thrive where a podocarpus might die, for example. Drainage can be installed in some cases – a French drain or small retention area can help mitigate water in a problem spot.

Undesirable fill soil can be a more difficult problem to deal with. Removing and replacing the soil is often too expensive and disruptive, though it can be an option in some cases. Amending the soil with organic matter can help make it more palatable to plants. In any case, a soil test can help to determine if there is a pH imbalance and what nutrients are present in the soil.

Chemical spills are thankfully rare, but the situation does arise occasionally. A normal soil test will not provide information on this – an agricultural testing lab may be able to test for residue, but this is often expensive and not guaranteed to produce results. Sometimes flushing the area with water or allowing nature time to break down the substance can work, but sometimes replacing the soil is the only option. Plant pathogens that persist in the soil, such as nematodes, or some fungal or bacterial diseases, are often difficult to remove even by replacing soil; the best option is to choose plants that are resistant to whatever disease or pest is present.

Often times, a soil test can be the most powerful and useful tool to help keep soil working for you instead of against you. Contact your local Extension office for information on soil testing. A good soil test will give you recommendations on how much lime to apply (if any is needed) to adjust the acidity to an appropriate level, as well as the amount of fertilizer needed for a particular type of plant.

For more information on soil testing, see our EDIS publication here: https://ask.ifas.ufl.edu/publication/SS494

To learn about irrigating to avoid soil problems, see this publication: https://ask.ifas.ufl.edu/publication/SS586

Evan Anderson

Walton County Horticulture Agent

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