Experts and BHG readers answer.
Planting Caladiums in July
If the caladiums were mine I would certainly go ahead and get them in the ground as soon as possible, as long as the tubers are firm and plump. It is doubtful that they will grow quite as big as those planted earlier in the season, but if you hold onto them without planting, it is a certainty that you won't get any growth at all this year. Since you are growing them primarily for their foliage, go ahead and enjoy them. They will not be harmed for next year, unless the tubers have already shrivelled up and dried out.