Yes, Osmocote is made to be used as a slow release plant food but it will release more quickly in high temps so follow the package instructions and make sure to mix the granules into the top few inches of soil rather than have them sit on top of the soil. In your case I would also add a mulch on top of the soil after using the Osmocote. A mulch will help to shade and cool the soil and conserve moisture and block out weeds. Keep growing - and Keep Cool, Marianne Binetti