A variety of vegetables, including cucumbers and different types of tomatoes, from columnist Anne Ditmer’s garden on St. Simons Island.

egetable gardening is a challenge in our coastal Zone 9A climate. Most of our gardening activities are determined by the heat, not by cold. In the hottest months, only a few vegetables will thrive. Northern gardeners may complain about long winters but those cold temperatures help to minimize insect and disease problems that seemingly thrive year round for us southern gardeners! Over the years, I’ve learned to let nature offer as many winning solutions as possible to enhance my attempts at controlling plant problems.

The first step in maintaining a healthy garden always starts below the soil surface. Fertile, organic, well-drained soil provides an environment where a host of small, medium and large organisms, soil microbes and plant roots all thrive. Improving our sandy soil with the addition of organic matter (compost, peat moss, animal manure, decomposed wood chips) goes a long way in ensuring success. Unfortunately, soil microbes work very rapidly in our climate and organic matter of this sort disappears quickly. A more permanent way to amend sandy soils is with biochar (basically charcoal), a product that significantly increases the soil’s ability to hold and release essential nutrients, which provides a high porosity environment for beneficial microbes and increases water retention. Biochar is made from agricultural wastes including plant stalks, straw, wood, and may also include manure and bones. Biochar is not something new. Native Americans of the Amazon Basin were known to change infertile, sandy soils into rich and sustainable fields of a soil type known as terra preta, created with charcoal, manure, bones, food waste, human feces, broken clay pots, etc. Microbes don’t eat biochar, meaning that once added to the soil, it stays there and its job is to hold and release nutrients in the soil for months. You can find recipes on making biochar using charcoal or coal dust to which you add moist animal manure and let it mature for 2-3 weeks. You can also purchase 100% biochar to which a nutrient source must be added or choose already enriched nutrient-charged biochar.

The second step in maintaining a healthy garden is to seek out locally grown seeds and plant varieties that have been proven to be more resistant to the pests, diseases and heat that cripple popular northern grown varieties. Seed sources tailored for gardening in the deep South include Victory Seed, Southern Exposure Seed Exchange, Sow True Seed, Baker Creek Heirloom Seeds and Johnny’s Selected Seeds. Not all your choices will be successful since each garden site is unique, but many will. I’ve come to learn that crops for the home garden (like squash, zucchini, tomato, bush bean and cucumber) planted in March produce prolific amounts of produce mid-May to mid-June but usually succumb to disease and insects as the summer continues. However, okra, eggplant, cow peas and peppers will continue strong through July, August and September. Sweet potato and pumpkin planted at the same time as the others can be harvested in early fall. Success is found in planting the right crop at the right time.

The third step is easier if the first two steps are accomplished. Make the garden inviting to beneficial insects like ladybugs, praying mantids, parasitic wasps, assassin bugs, mite predators, beneficial nematodes and lacewings. All of these can be purchased and introduced to the garden. Avoid harmful chemical control methods which kill both the good and the bad, upsetting nature’s balance. If you must spray, choose an OMRI listed organic means of control. Products containing Bt for caterpillar control, NEEM oil, mineral oil (TriTek), or pyrethrin can work, although weekly repeat applications are usually needed.

In addition to the above, choose a site that offers some filtered shade during the hottest parts of the day and one that allows for good air movement to reduce fungal diseases. Be sure plants have adequate nutrition (I have soil and foliar samples examined to see what is in the soil as well as what the plants are actually taking up from the soil) and sufficient water. Remain vigilant, looking for signs of problems so that they can be tackled before they get out of control.

Long ago, I received some great advice. The best gardening information is often passed “across the fence.” In other words, experienced fellow gardeners who live near you and deal with similar conditions usually love to share gardening tips and sometimes offer pass-along plants and seeds from those plants proven to be extremely successful in their gardens. The local cooperative extension office can provide many free bulletins on a large variety of topics and the local agent is more than willing to offer advice!