Ask Mr. Smarty Plants

Okay, we're going to play Plant Detective, and first we'll scare you to death with some stuff that probably isn't the problem. In fact, these diseases are much more likely to show up in a commercial growing operation, where cultural practices are not as easy to control and disease can quickly spread. So, take a look at this website on The Pests and Diseases of Basil. From your description, we really don't think any of these fungal diseases are affecting your basil. If you determine that one of them IS the problem, the recommendation is to quickly remove the plant and its soil from your property, along with any other plants of the mint family that appear similarly affected.

But let's be more optimistic and say just this one pot is having a problem, since you say the one next to it, in the same cultural conditions, is doing fine. So, maybe it's just that particular pot. Unfortunately, shriveled leaves can be attributed to too much water, too little water, too much sun, not enough sun-well, you get the picture. Is the pot being watered regularly, now that summer is truly upon us? Is it draining well? If the drain hole is plugged up, the roots could be sitting in a swamp in the bottom. Only swamp plants like their roots in a swamp. On the other hand, if the soil gets too dry between waterings, water will just rush through the dry soil without soaking in and go out the hole. Our basil on the back porch, even with daily waterings, seems to be drooping by the middle of the day now that real summer heat and dryness have come to Texas, even with regular daily watering. Is the plant in a plastic pot? Those things can get flaming hot in the sun, and really toast a little plant's roots. Maybe a little midday shade would make all your basils happier. Yellowed leaves toward the bottom of the bush mean it needs more sun and/or less fertilizer.

Okay, let's be honest, here. We really don't know what is happening to your basil. If it looks like it's surviving and doesn't have some dread disease, we'd suggest doing a little pruning to make it more bushy. To extend the life of a basil plant, the flowers should be nipped off as soon as they appear. Some trimming down and thinning out will give the plant less leaf surface to evaporate moisture. And, let's get real. Basil is an annual that will go home to its Fathers at the first frost. If it insists on being a prima donna and sulking no matter what you do for it, ignore it. It can be replaced.