Indoor Plant Info: Q&A


Indoor Plant Information

Horticultural Help provides professional information on the care of indoor plants, in most cases without charge. Much of this information is not available in books or elsewhere online. The information provided here is written in plain English and provides not just an answer, but a deeper explanation behind that answer. What you read here may surprise you and conflict with what you have heard and read elsewhere.

Here you will find professional indoor plant care information based on 30 years of professional hands-on experience caring for indoor plants in office and residences. These are environments similar to your home and office. Other sources of indoor plant care information rely on experience gained in controlled environments such as greenhouses, nurseries and tropical rainforests. Searches online will yield non-professional information that is anecdotal and rarely based on solid research.

Make sure your indoor plants get enough light. Most folks overestimate the available light in their homes. Even low light plants need to be within 6 to 8 feet of a sunny, uncovered window. Most other indoor plants must be within a couple of feet of a sunny window. The window must be uncovered throughout the daylight hours. Before you purchase a plant, evaluate the available light and select a plant based on that. If you have only low light, then you are limited to low light plant species (see Indoor Plant Bulletin No. 9 for a list of low light plants). If you have better light, then your plant options expand. Order a free copy of my Indoor Plant Bulletin No. 3 to help you assess light so you can make better plant choices.
Houseplants need high humidity, right? Wrong. Most common houseplants have proven to do quite well in very dry, indoor winter air even though these same plants are native to naturally humid environments. As long as you keep the roots well supplied with water, most indoor plants will do fine without added humidity. Daily misting to increase humidity is a waste of time. At best it raises humidity for 10 minutes out of a 24-hour day. If you want to increase humidity, buy a humidifier (your skin and furniture will also benefit) or set up humidity pebble trays under your plants.
Everyone likes to fertilize. Presumably good health and vigorous growth are virtually guaranteed when you fertilize. Here is another surprise: fertilizer is vastly over-rated and guarantees neither health nor growth. The truth is that plants use nutrients in miniscule quantities. Good potting soils have an abundance of nutrients that will last for several years or more without any supplements. Light and proper watering are what will determine the health and growth rate of your plants. So if you want to skip the fertilizer, your plants will not notice. Finally, never use fertilizer as medicine to fix ailing plants. It is not medicine and will only aggravate the problem. Still not convinced? Learn all the specifics of plant nutrients, fertilizers and which brand you should choose by ordering a free copy of<em> Indoor Plant Bulletin No.8.
There is a widespread notion that plants steal oxygen from the air at night and should not be used in bedrooms. Plants use carbon dioxide during the day to produce photosynthesis and oxygen that is emitted into the air. At night when there is no light for photosynthesis, the process is reversed and plants use a slight amount of oxygen. However, the oxygen debt at night is far less than the oxygen added during the day. So feel free to keep plants in your bedroom as long as there is enough light to keep them growing. The plants will not only add oxygen, but they help filter air pollutants
You may be surprised to learn that most indoor plants do NOT have a dormant period in the winter. Indoor plants are native to tropical regions where temperatures and light are fairy constant throughout the year. Although the hours of daylight available for plants indoors are shorter in winter, the reduction in light slows plant growth only a bit. Because they are non-seasonal, most indoor plants can be pruned and repotted at any time of year.

Here are the names of some common indoor flowering plants that DO have dormant or semi-dormant periods, usually in the fall: Amaryllis (dry), Anthurium (cool), Azalea (cool), Camellia (cool), Christmas Cactus (cold), Gardenia (cool), Gloxinia (dry), Hibiscus (cool and dry), Kalanchoe (short days), Oxalis (dry), and Poinsettia (short days).

Questions & Answers

Over the past 15 years, indoor plant expert Will Creed has answered thousands of questions online and via email. In this Knowledge Base Q&A format you can search for and find the various topics that relate to your concerns or interests. Simply type your topic into the search box on this page.


If you cannot find your answer here, you have several other options:

Search Knowledge Base by Keyword


Created by Studio 545 Website Design

© 2023 Horticultural Help