Gardening Methods

why are my potted plants not doing well in se florida?

Recently I relocated to Se Fl. from New England. I was always quite successful w/container gardening up north, but here in Fl. things are not going as well.
Here’s a short list. cherry Tomatoes, oxalis, sweet alyssum, Passionflower, alpine strawberry, gr. pepper, asstd succulents, and cacti, nasturtium, morning glory, anthurium, etc. everything that requires direct sun, gets approx. 7-9 hrs, western exp. those needing shade, i cover, Iwater and feed, I use well draining clay pots, but everything, seems to peak i.e. they hit a point where they just become stunted. No coaxing seems to help, as these plants all seem to be in some sort of limbo, sending me to black thumb purgatory. any advice? (Artificial is out of the question….for now, lol)

A key statement you make in your question is, “I use well drained clay pots”. In the Northeast, during the hottest months, I often need to water my unglazed clay pots 4 times a day or the plants suffer (depending on their size and what I have planted in them). The plastic containers I use need to be watered once or twice a day – but I am never able to skip a day. If I do, by day two the plants are beginning to wilt, if it is particularly hot. Since clay pots loss moisture from the top and sided and Southeastern Florida is VERY HOT AND HUMID, especially at this time of year – and I have often spent summers there – I would assume the problem is lack of moisture and can be one or all of the following problems.
Either the soil mix you are using in the pots does not have enough loam and/or peat to retain moisture until the next watering.
You are not watering thoroughly enough.
You are not watering often enough.
Or at some point the soil dried out enough that there are pockets underneath the surface soil that have remained “un-wetable” – so when you DO water, the water is bypassing those areas and no matter how much you water – there is soil within the pot that stays dry.
Now the solutions: Water the plants THOROUGHLY by hand with water, to which you have added a half a teaspoon of dish detergent per gallon of water (use a proper measuring spoon). Wait twenty minutes and do it again. The detergent will work as a wetting agent by breaking the surface tension of the soil and any dry areas beneath the surface, that are not visibly, will become re-saturated/moist. Then make sure you water, at the very least, twice-a-day – morning and evening, on the hottest days. I have no doubt; you will see an improvement within a week. Just make sure the soil does not ever get to the point of less than barely moist again. If it does, you will need to use the detergent/water solution again to make sure ALL the soil within the pots is absorbing water. Good luck – Both with your plants and the headache I must have given you with this dissertation.

Barbara Aziz, Ann Leggett & Francis. Boyle April 1992