The experience of indoor gardening with tropical plants helps shorten the "longest season" on the calendar.
As with your outdoor garden, it is important to provide the proper care and conditions for your indoor plants and be aware that these requirements will changes as each month passes.
As plants adjust to the lower light levels and lower humidity of winter, it is normal to observe some leaf drop. The reduced light levels experienced during the winter months will also mean plants will not likely flower much – if at all!
Reduced flowering is a sign that your indoor tropical plants are entirely dormant or semi-dormant. During rest periods, plants require less fertilization. Use fertilizer half the strength and half as often. You could use a half strength 20-20-20 water soluble fertilizer all winter. Keep in mind that the care given to a houseplant during this dormant period is aimed at maintenance rather than growth.
There are plants, such as African Violets, which do not require a period of dormancy. They can be fid year-round each time they are watered. Fertilizing consistently will product better symmetrical growth. There are specific fertilizers formulated for consistent feeding programs to avoid over fertilizing and damaging plant roots.
Many indoor plants prefer to grow in a pot that appears "too small". This is especially true of succulents and cacti, which actually prefer to be "under potted". However, once a tropical plant is truly pot-bound, it is usually necessary to move this plant into a larger container. A pot-bound plant has visible roots growing through the drainage hold and roots growing through the surface of the soil. If you plant seems to require frequent watering, there is probably insufficient soil left in the post to retain enough moisture. You should move up to a pot that is only one or two inches larger in diameter that the previous one. A pot that’s too large will contain too much soil for the root structure, which will retain too much moisture and may cause roots to rot over time. Severely pot-bound plants will have roots which are circling around the container. Once removed from their original pot, the roots should be cut with a sharp knife from the top to the bottom of the root ball. This will encourage new root growth and help roots grow into the new potting soil.
As you care for your tropical plants this winter, keep in mind that cuttings can be rooted and used as annuals in your garden next spring. Many garden centers are selling tropicals as annuals and they are growing in popularity. The next time your prune back your trailing Pathos or spider plant, imagine how beautiful those cuttings will look growing in your container gardens next season.