If the leaves of the plant seem reddish or yellow, or if they curl up, a close inspection will generally disclose that the plants are infested by a very small green insect, or else with red spider, either of which must be destroyed. For this purpose, scald some common tobacco with water until the latter is colored yellow, and when cold, sprinkle the leaves of the plants with it. It is a good plan to pass the stems and leaves of the plants between the fingers, and to then shake the plant and well water the bed immediately afterward; the latter operation destroys a large proportion of the insects shaken from the plant.