Houseplants need varying amounts of water and fertilizer at different times of the year. They need the most during summer when light levels are high and days are long. They need the least during the short days of winter. The primary reason for this is light. Light produces the fuel for plant growth. More light allows more growth, which results in a greater demand for water and nutrients. When light is limiting, the need for water and nutrients decreases dramatically. Therefore, it becomes easy to overwater and overfertilize during the winter months. Excess water and fertilizer can harm a plant by damaging the root system. Overwatering can suffocate roots by eliminating oxygen and excess fertilizer can burn roots. Therefore, it is best not to fertilize at all during the middle of winter (December-January) and to fertilize sparingly during November and February (maybe 1/4 a normal rate).
It is never wise to water on a set schedule. Rather, allow the potting soil to tell you when watering is needed. Check to see if the soil is moist 1-inch deep by inserting your finger into the potting mix. Don’t water unless the mix is dry. (Ward Upham)
