How to care for indoor houseplants

For as long as I can remember, indoor houseplants have been part of my décor. However, I never really thought of them as ‘décor’. Today, we have such beautiful plant varieties and containers available, that plants have really become part of the indoor décor. Indoor houseplants not only add beauty to your home, but there are also health benefits.

• Based upon a Clean Air Study performed by NASA, plants help to clear the air of pollutants.
• Plants boost healing. Think about when you bring a plant to someone in the hospital.
• The simple act of caring for plants can reduce stress.

This post focuses on how to care for indoor houseplants with a focus on foliage plants as opposed to flowering houseplants.

Key requirements to care for indoor foliage houseplants

My belief is that anyone can care for indoor houseplants. No, you don’t have to have a ‘green thumb’ to care for houseplants. While there are several care requirements, the two most important are light and moisture. If you get these two right, your plant should do simply fine.

• Light –Plants derive their energy from photosynthesis and photosynthesis depends upon light. When you purchase an indoor plant, there should be a reference on the label regarding light requirements. Light requirements range from low light plants to bright light plants. However, even low light plants need light to thrive. Foliage plants do best when placed near a north-facing window or in a window where the sunlight is diffused through a curtain.
• Water – plants should be watered when they need water. Sounds simple enough. The question is how to determine when to water. There are two practices I recommend. First, look at the soil. Dry soil becomes lighter in color and may pull away from the sides of the container. Second, stick your finger approximately 2-inches into the soil. If the soil looks and feels dry, then water. Here are a few other watering considerations:
  • There are two methods of watering.
    • Water the plant from the top. In this method, it is good to pour water until the water flows out of the drainage holes at the bottom of the container. When watering using this method, try not to get water on the leaves of the plant. Also, dump any water that may remain in the saucer.
    • Water the plant from the bottom. In this method, the container is placed into a bowl of water and the water is absorbed thru the drainage hole. When the top of the soil is moist, then the plant can be taken out of the bowl of water.
  • Tap water is generally fine to use. Rainwater can also be used. I personally like to use filtered water. Water that has been treated by a water softener should not be used because it contains high amounts of salt.
  • Water during the day as opposed to at night to ensure that any water on the leaves has time to evaporate.
  • Houseplants have a period of time when growth slows. For me in USDA gardening zone 6a, that occurs during the fall and winter. When growth slows, plants need less water.

Additional care considerations

Here are a few additional considerations to care for indoor houseplants.

• Containers – The most important consideration for containers is the requirement to have drainage holes. While not ideal, you can get around this requirement by placing small pebbles or gravel at the bottom of a container. Without drainage holes, it’s so difficult to determine if there is standing water at the bottom of the container.
• Fertilizer – Always read and follow the directions on any fertilizer you purchase. Here are a few considerations when choosing a fertilizer:
  • Every fertilizer will have a series of numbers such as 5-5-5 or 3-2-1 on the label. These numbers indicate the percentage of nitrogen, phosphorus, and potassium (N-P-K) contained within the fertilizer. Most foliage houseplants do well with a balanced fertilizer. Balanced simply means that there is an equal amount of each nutrient (nitrogen, phosphorus, and potassium) in the fertilizer such as 20-20-20.
  • Fertilizers can take the form of either liquid, granular, or slow release. I like using a slow-release fertilizer that can be mixed into the soil. This takes a lot of the guesswork out of remembering when to fertilize.
  • Similar to watering requirements, fertilizer requirements decrease when plant growth slows.
• Temperature – most foliage plants can tolerate temperature inside a home. Ideal indoor temperatures are between 65 – 70 degrees F. Tip: Don’t place plants where there is a draft from heat or air conditioning vents.
• Humidity – Plants benefit from an increase in humidity. However, this can be difficult to maintain inside your home. I recommend two options to increase humidity.
  • Place small pebbles or gravel in the saucer of the plant container and fill with water.
  • Group multiple plants together. Plants benefit from being around other plants.

Repotting considerations

One last recommendation. While there are different points of view on this topic, I recommend repotting new houseplants after you bring them home. However, if the plant is in a decorative container and the leaves and roots look healthy, then leave in the current container. Here is the process I follow when repotting:

• Choose a container 1-2 inches larger than the current container. For example, if you purchase a plant in a 4-inch container, transplant into a 6-inch container. While it can be tempting to transplant into a much larger container, don’t. This should always be the approach when repotting.
• Remove as much of the soil from the roots of the plant to be repotted.
• Fill the container halfway with new potting soil.
• Add a slow-release fertilizer to the soil.
• Place the new plant into the soil and then fill around. Gently compress the soil around the plant. The foliage of the plant should sit equal with the rim of the container.
• Water thoroughly.

Diagnosing Houseplant Problems

Here are two great resources for dealing with pests and disease in indoor house plants.

• Pests: Common Houseplant Insects and Related Pests
• Other problems: Houseplant Problems

You might also find the following post to be of interest:

• The complete guide to caring for African Violets