Wintertime Indoor Plant Care

Wintertime brings many changes to the garden, including cooler temperatures, more moisture, and beautiful, bare-branched silhouettes. As gardeners, our tasks become fewer and less frequent, and we're able to enjoy our outdoor spaces from the warmth of our homes. While we may miss our garden plants, we still have the opportunity to care for our green family members indoors. Houseplants are not immune to wintertime changes in heat and air moisture, even though they live in temperature-controlled spaces. These indoor plants, whether they are kept inside year-round or are just visiting over the cooler winter months, can be affected by several stressors. Evening chills, dry air, and shorter days are all factors that come into play for houseplants in the wintertime, and learning how to tweak care practices during this season can go a long way in ensuring indoor plants stay healthy until spring.

Indoor plants vary in their care needs in wintertime depending on their species, so some research will be necessary to provide the best care possible. The following tips and tricks will provide you with a general guideline. In general, the goal is to attempt to mimic the winter conditions in the regions to which indoor plants are native. For example, rainforest-dwelling plants experience little change between summer and winter conditions, and will not have the same dormancy period as plants that hail from more temperate regions.

Water

In wintertime, most indoor plants will require less water than they do at other times of the year. While it is true that the air tends to be more dry during this time, most plants are slowing down and experiencing some level of dormancy. Some indoor plants will go completely dormant, and not put on any growth at all over winter. Because of this, plants will require less water to keep hydrated. Applying the same amount of water at the same frequency as the rest of the year can result in overwatering and lead to root rot. Some drought-tolerant indoor plants, like cacti and succulents, may not need any water at all, while some tropicals may still require more regular irrigation. A good rule of thumb is to stick a finger down into the soil of your potted indoor plant to decide whether it needs water. If the soil feels dry an inch or two below the surface, it is a good indicator that water can be applied. The water that is used to irrigate houseplants should be room-temperature; using water that is too cold can actually shock the roots of indoor plants.

Humidity

One of the biggest changes in the winter for indoor plants is ambient humidity. Using the heater in climate-controlled spaces lowers humidity levels, which can drop by 10 to 20 percent. Most indoor plants that hail from more tropical regions require humidity to stay around 50 percent. Setting up a humidifier can help to increase air moisture, especially if it is situated close to where the indoor plants are kept. Grouping plants together during this time of the year can help, as well. They naturally release moisture through transpiration, and will provide more humidity for each other when grouped. Bathrooms and kitchens are great places to group plants, as they generally tend to be a bit more humid than other areas of the home.

Misting plants with a spray bottle by hand is only a temporary blast of moisture, and does not help to increase the humidity around plants. To be effective, a plant mister can be used multiple times per day to be effective. The main issue with these methods is that moisture evaporates quickly in indoor spaces in wintertime due to the use of climate-control mechanisms (like heaters). If you only have a couple of plants to care for, misting can be an option, but it needs to be done diligently, and a plant care surrogate will need to be hired for any time you spend away from the home. 

Temperature

As stated above, most indoor plants tend to be from tropical rainforest areas of the globe, and prefer daytime temperatures between 65 and 75 degrees Fahrenheit. To mimic these conditions for houseplants, keep them away from drafty areas (like doors and windows that are opened frequently), and heat sources (like space heaters, radiators, ovens, fireplaces, and electronic devices). Fluctuations in temperature should be avoided, and keeping plants in a non-drafty, climate-controlled space can go a long way in preventing damage to foliage and other plant parts.

Light

In wintertime, there are fewer hours of sunlight, and rays are also less intense. Houseplants can be relocated during wintertime so that they are closer to light sources from outdoors, or sunlight can be supplemented using grow lights. Good spaces to choose for placing indoor plants are inside windows that face south or west, though these spots can also be a little drafty, so use your best judgement when moving them. Make sure to rotate pots about a quarter of a turn whenever they are watered. This will ensure that they do not develop bald spots and will produce foliage evenly. Otherwise, branches may begin to stretch and become a bit leggy trying to reach a more sufficient light source. It is also a great idea to wipe down leaves regularly (not just during the wintertime, but year-round) in order to maximize the photosynthetic potential of leaves. To do this, simply run a wet cloth across leaves.

If a supplemental grow light is employed over the winter months and plants are not receiving any actual rays from the sun, they will need to be turned on for longer than the plant would regularly receive sunlight. For example, if a plant requires about six hours of direct sun per day, it may need as much as between 12 and 14 hours of supplemental light to provide an equal amount of energy. This is due to the fact that grow lights are considerably less powerful than direct sun, so plants will need to be exposed to them for longer amounts of time to receive the same amount of energy.

Food

Fertilizing houseplants is typically necessary, as they do not get the natural breakdown of forest floor material providing nutrients for growth. During the winter, however, fertilizing activities can be greatly lessened, or even discontinued. Feeding houseplants during winter will not allow them to enter any period of dormancy, which is typically a required yearly process for plant health. When springtime rolls around again, feedings can recommence. The exception to this rule is that some tropical plants, especially climbing or vining plants, will still require light feedings through the cooler months.

By keeping these points in mind, wintertime care for houseplants will be a breeze!