Question: Which lavender cultivars can I grow in northwest Florida (the panhandle)? Every time I try to grow some down here it gets sick and never comes back.
Answer: Lavender is notoriously difficult to establish in a Southern garden. You may think its Mediterranean and Middle Eastern origins would make it perfect for Florida, but high humidity and rainfall wreak havoc on lavender’s foliage (fungus) and roots (rot).
Good drainage is extremely important. Scout out a spot in full sun that boasts well-drained soil, preferably slightly raised above the rest of the garden. Boost drainage with pea gravel. Dig a hole with a circumference equivalent to the mature plant’s spread, mix pea gravel into the removed soil, and then place the rocky soil back into the planting hole. After planting, mulch the surface with about 1 inch of pea gravel. To deter rot, keep the plant’s woody base clear of leaves and other material and provide plenty of space between plants for healthy air flow.
Lavender prefers a slightly alkaline pH. If you live in or near one of Florida’s piney woods, your soil may be highly acidic, so neutralize it by adding calcium carbonate or dolomite.
Choose cultivars carefully. Avoid English lavenders (Lavandula angustifolia) and instead opt for Spanish (L. stoechas), which is pictured above, and French (L. dentata) cultivars. Although no heirloom lavenders are especially suited to your climate’s heat and humidity, there’s a promising hybrid: Lavandula x intermedia (lavandin) called ‘Phenomenal’ that is earning rave reviews for its heat tolerance and resistance to common root and foliar diseases.
Lavender can be grown in containers, too, where you’ll have complete control of soil pH and drainage. - Rebecca Martin, organic gardening expert and managing editor of Mother Earth News magazine