In the middle of summer, it’s so easy to get caught up in yard jobs that we forget to take care of our houseplants.
But just like their outdoor cousins, indoor plants grow well in the summer and need similar levels of care and attention to keep them thriving.
Indoor green spaces have become increasingly popular over the past few years, and houseplants are known for their properties in cleaning the air and improving our health, well-being and happiness.
Caring for houseplants in summer: our five essential tips
By following our five expert tips, and avoiding the most common indoor plant mistakes, you’ll keep your houseplants thriving all summer long and ensure they’re strong and healthy as we head into the fall and winter.
1. Getting rid of fungus gnats
Fungus gnats can be a huge problem for houseplants, being more annoying to the grower than the plants themselves. Also called Scariad flies, these are small black insects that can be brought indoors in moist soil or on plants outside.
The adults do not cause much harm, but they lay their eggs in moist soil and the larvae feed on plant roots. They are especially dangerous for young seedlings because the damage caused by the worms stresses the plants and may cause them to wilt or even die completely.
There are several ways to get rid of adult insects and thus break the mosquito life cycle. One way is to kill them with a chemical spray, such as Garden Safe Houseplant and Garden Insect Killer, available on Amazon. If you are using this indoors, make sure the room is well ventilated and that there are no children or pets around.
Organic control methods include making sure to allow potting soil to dry before each watering, and using a peppermint oil-based product such as Mighty Mint 32oz Peppermint Plant Protection Spray, also found on Amazon.
If you prefer a home remedy, a cheap, safe and highly effective way to catch and kill fungus gnats is to fill a bottle cap with a few drops of water mixed with honey or maple syrup and place it on the potting soil. The sweetness of the mixture attracts adult mosquitoes, causing them to fly and drown. Change the cover every few days and your fungus gnat problem will be a thing of the past!
We do not recommend using sticky fly trap sheets as they are indiscriminate and will kill spiders and other beneficial monsters that help keep our homes free of unwanted insects.
2. Remove damaged leaves
We all want our houseplants to look lush, green, and healthy, but sometimes their leaves turn brown and dry out, reducing their visual appeal. This is because many indoor plants originate in temperate or tropical regions, where the weather is humid and humidity is high.
However, air conditioning and central heating in our homes dry out the air, and so our plants suffer. The exception to this rule is the bathroom, as the dim light and high humidity make it one of the best places for a wide range of plants.
Once individual leaves begin to turn brown, your only option is to remove them from the base, using thin-bladed plant snips such as the Gartol Micro-Tip Pruning Snips on Amazon, which are ideal for getting between dense stems at the base of plants. Removing dead and damaged leaves makes room for new growth, but be careful not to cut off too many at once.
If most of the leaves are damaged, remove a few, wait for vigorous new growth to come in, then remove a few until all the old leaves are gone and the plant has lush new foliage.
Once the leaves start turning brown, removing them is your only option, but there are several things you can do to prevent this from happening in the first place.
The first is to maintain a humid atmosphere around your plant. Do this by placing your plant on a tray or pot with a layer of gravel, such as volcanic rock pebbles found in the Amazon, at the base that is kept constantly moist.
When moisture evaporates, it creates a humid microclimate around plants, which is beneficial for their health. Then spray the leaves with lime-free water or rainwater every few days (hard water can leave white, chalky spots on the leaves). Use a mister like the Flairosol spray bottle found on Amazon.
Finally, avoid placing your plants near sources of direct heat or cold air, such as radiators, air conditioning units, and open fires.
3. Fertilize and water regularly
Summer is the peak growth period for most houseplants, so you need to feed and water them accordingly.
The best water to use is harvested rainwater because tap water contains minerals and chemicals that can build up in the potting soil and harm your plants.
If you don’t have access to a rain barrel, collect tap water in a jug and let it sit for 24-48 hours until most of the chemicals dissipate.
Water the plant every few days, or when the potting soil feels dry to the touch. Do not overwater or leave plants standing in water as this will saturate the soil, releasing oxygen and “drowning” the roots.
Cacti and succulents need very little feeding and watering, and if the soil remains wet it can lead to rotting of the base.
Feed your plants every two weeks with a houseplant fertilizer such as Easy Peasy Liquid All Purpose Plant Food that contains the appropriate nutrients. To make feeding easier, use fertilizer spikes, such as Miracle-Gro Indoor Plant Food Spikes, which will release nutrients at regular intervals. Both are available on Amazon.
Orchids need specific nutrients that can be given in liquid form, like this orchid plant food, which will also benefit acid-loving houseplants like African violets, gardenias, and monstera, or a foliar spray like this weekly fertilizer spray from Southside, both on Amazon.
Cactus and succulents need monthly feedings as they grow, and I like to use this slow-release feeder from The Grow Co, available on Amazon.
4. Your plants are vacation-resistant
It’s vacation time, and unless you have a house elf on your staff, your houseplants will be left to fend for themselves while you’re gone.
There’s always a lot to do and think about before going on vacation, but with a little thought and planning, you’ll be fine while you’re gone.
Water and feed them before they go, then place them on trays of moist gravel to improve the humidity around their leaves. I often leave ours in the shower with a little water. Light and moisture create a warm, humid atmosphere that suits them.
You can also place plants on a capillary mat, like this 2-Piece Automatic Plant Watering Mat from Amazon. Place one end in a bowl of water and the material will absorb enough moisture to keep the plant compost moist.
If you close the curtains for safety, move the plants to a room with more light, but keep them out of direct sunlight that can burn their leaves.
Deadhead any flowers likely to pass by during your absence. This way you’ll come home to some hopeful new buds instead of a depressing bunch of brown petals!
5. Provide leave for your plants
While we enjoy our vacations, it seems only fair that houseplants spend some time outside, too. Many indoor plants will thrive in a warm patio. Any rain will wash the dust off its leaves and the breeze will help strengthen its stems and roots.
Don’t rush to move them outside though. It is best to wait until night temperatures exceed 50 degrees Celsius, because most houseplants are varieties of tropical and temperate climates and do not like the cold. Likewise, bring them back indoors in the fall when temperatures begin to drop again.
When it’s warm enough in the yard, start moving the plants outside. For the first few days, keep them in a shaded, protected area and then gradually increase the sunlight each day.
If you expose them immediately to full sun they run the risk of leaf burn and some varieties, such as weeping figs and hibiscus, may drop some leaves at first, although more will grow once they acclimate. If you don’t have any shaded areas, create a sheltered area using garden shade cloth, widely available on Amazon.
You may need to water and fertilize your plants more often because the sun and wind will dry out the potting soil, and the increased warmth and light will encourage them to have a growth spurt.
Test the moisture of the compost before watering to avoid overwatering, and feed with an all-purpose liquid fertilizer added to the water every 10 days. You can make life easier with fertilizer spikes and watering tools like these ones on Amazon. Alternatively, fill a bottle with water and general liquid fertilizer and top with a Terracotta Vacation Plant Waterer available on Amazon. Insert the spike into potting soil and it will slowly release its contents, feeding and watering your plants at the same time.
It’s always important to know when to water, but especially when watering plants in hot weather, avoid doing so at the hottest times of the day and make sure you soak the plants well rather than just a trickle.
Watch out for pests, too, especially vine weevils that eat the roots and aphids that suck the sap. There are several ways to get rid of insects in potting soil, and when the plants are in the yard it is best to let natural predators take care of the pests that live in the leaves, then you can treat the rest with an organic control such as nataria neem. Spray the oil on Amazon when bringing plants back indoors in the fall.
Open windows allow dust, debris, and pests into the home, many of which will land on your houseplants.
This can cause the leaves to become dull and the plants to suffer, and one of the easiest ways to prevent this and keep plants healthy with shiny leaves is to wipe the leaves with a soft, damp cloth dipped in lukewarm water.