It depends. To determine if your plant needs more light, try observing it for a few weeks. Is the new growth lanky and thin? Is the plant shedding lots of leaves? Is it looking lack luster and unhealthy? Is the soil always wet even though you haven’t watered it for a couple weeks? These are all signs that your plant may want more light.
The type of plant and its placement usually determines whether or not supplemental light is necessary, but it is also important to consider the time of year, especially since our Alaskan winters are so long and dark.
The following plants tend to need very bright light and lots of it:
• Ficus trees
• Lipstick vines
• Euphorbias and cactus
• Most flowering plants
• Some palms
• Birds of paradise
The plants listed above should be fine most of the year in a south window or under the bright fluorescent lights in an office. During our dark winters, however, the plants by windows may not get the amount of light they need. Setting up supplemental lights or moving the plants to a bright artificially lit location may be necessary to maintain their fullness and health.
The following plants are all tolerant of lower light situations:
• Peace lilies
• Chinese evergreens
• Cast iron plants
• ZZ plants
• Some palms
• Snake plant
These low light-tolerant plants are happy in an east, west, or north window, and usually do not need any supplemental winter light. They will also grow well in an office lit with fluorescent lights.
What types of light bulbs are best for houseplants?
If you’ve decided you need additional light for your plants there is no need purchase expensive grow lights. Fluorescent tubes or compact bulbs work just fine. Incandescent bulbs don’t do much for plants, however, so save them for your favorite reading lamp.
If using fluorescent lights, be sure to leave them on for at least 8 hours during the winter. Get them close to the plants if you can. During summer months you can reduce the duration you have the lights on or turn them off altogether depending on your specific environment.