We all know that houseplants thrive in the spring and summer – when the days are long and the sun is plentiful – but what about the fall and winter? Here at The Sill, we tend to argue that winter is houseplant season, and fall is us gearing up for it. This might seem a bit crazy, considering the environmental conditions winter brings – think short, cold, overcast days here in New York City – but we ask you, in what season are houseplants more beneficial to our overall health and wellbeing?!
As author and renowned plant authority Tovah Martin remarks, “I’ve never had the opportunity to explore whether I am prone to Seasonal Affective Disorder. With all this greenery around, I never feel the full brunt of winter. Sure, my back aches from shoveling snow and my fingers are swollen from chilblains. But my spirit is warmed by all the growing things performing around me.”
And with that sentiment, we decided to bring you as much fall plant care tips and tricks as possible this September. In the hopes that you, too, can dread the changes that are coming our way just a tiny bit less than usual. To kick it off, we’ve reached out to The Houseplant Guru herself, Lisa Eldred Steinkopf (even her license plate says houseplant), to share her top tips for keeping your houseplants healthy and happy as fall sets in.
My Fall Plant Care – Lisa Eldred Steinkopf
As the kids get ready for school and the garden outside is winding down, it is time to give some love and attention to our indoor plants. They are beginning to slow down their processes with the decreasing day length and many people are beginning to bring their summer vacationing houseplants back inside before the cold weather begins.
If your plants have been outside for the summer, they are used to a high light situation. Even if they have resided under a tree or in the shade outside, odds are the level of light inside your home is still much lower than the level of light outside. Acclimatization is key when bringing your plants back into the dim interior of your home, and now is the time to start that process if you haven’t already. What is acclimatization? It is the process of giving time to a living organism (plants) to adjust to a new situation. So how do you do that? Take your plant from the light situation it is in, and move it gradually to lower light situations for a couple of weeks so that it can gradually get used to the lower light it will be encountering in your home. For example, move a full sun plant into ½ day shade and then to full shade, such as the north side of the house or under a densely branched tree or shrub, over a two week time period. (P.S. This rule of acclimatization should also be followed when bring your houseplants from inside to outside in the springtime.)
Okay, so you’ve acclimatized your plants. What next? Before you bring your plants in the door, examine them for any signs of pests, especially if you have other plants inside that did not spend the summer outdoors. Nothing is worse than bringing scale, mealybugs, or spider mites inside and infecting your other houseplants. Check the undersides of the leaves, the crevices between leaves and stems, and also the soil. The first line of defense is to spray the plant with a hard, but not damaging, stream of water and flood the pot with water, hoping anything that may be living there comes to the top or runs out the bottom drainage holes. Completely changing out the plant’s soil is also a practice some people have adopted. Additionally, there are products that can be used to help make sure any unwanted visitors are executed before bringing the plant inside. A systemic insecticide used in the soil will spread up into the plant, making it toxic to insects. You can also use a Neem oil spray which is a fungicide, miticide, and insecticide in one, so it may help with more than one problem. Insecticidal soap may be used as well. Find what works for you and your plants, and make sure you read all the directions on the label and follow them. Remember – more is never better for your plants!
What next? Maybe something you haven’t thought of – wash your windows! Windows collect a lot of dirt from rain, dust, and smog, all summer long. What a difference it makes to have clean windows and it will benefit your plants immensely. Also, wash the plants themselves. Take them to the shower and really give them a good cleaning on a regular basis all year. The dust on your windows and plants interferes with their life sustaining photosynthetic processes. Light can’t reach the leaf cells when dirt and grime get in the way.
Because here in the Northern hemisphere, our plants slow down their processes as the day length shortens, we do not need to fertilize our plants from late September through February. At this time, fertilizing your plants for the last time is recommended. Whether you choose to use a synthetic or organic fertilizer, my rule of thumb is to use full strength every 4th watering or ¼ strength every watering. And like before, more is never better.
Another thing to consider as we bring our plants indoors for the fall/winter seasons are the heat vents spewing their hot air onto our plants. Whereas it makes us comfortable, our plants aren’t as happy with the situation. Although most plants do prefer warmer temperatures, the hot air of a heat vent is drying to the plants. Even though there is less light and their processes have slowed down, the hot air of a heater will suck the moisture right out of the plants. Therefore, when we first bring in our plants from their summer outdoors, they may need more water than usual. Misting is often recommended, but that is a very temporary fix, and one I don’t necessarily recommend. Instead, I set my plants on a pebble tray filled with water which will raise the humidity around the plant on a more permanent basis and offset the drying atmosphere of the heat vent. Just make sure the bottom of the planter is not submerged in the water.
With these few tips, I hope you can get your plants through the winter without any casualties. You can keep your houseplants happy and healthy by doing a few extra things in the fall, as you and your plants get ready for a long winter.