Last updated on October 25th, 2016
REPEAT AFTER ME: “Only the healthy houseplant is decorative, and only the decorative plant is worthy of display.” Ferns with brown, withered fronds, geraniums with sick, yellowed foliage, and pitiful vines bearing only a few leaves at their very tips can’t possibly enhance the mood of a room. And here are seven rules that will keep your potted friends looking their decorative best:
1. Give them bright light or sun. The old adage “foliage plants require light; flowering plants demand sun,” is still a good rule to follow, but there are exceptions. Impatiens, wax begonias, cyclamen and primula can bloom with almost no sun at all, and certain green-growers, including ferns and vines, can benefit from direct sun in winter. But no growth is possible in darkness; plants require light to manufacture food.
2. Aim for cool temperatures. The same jasmine that blooms in a 50-degree greenhouse is sure to fail in your 70-degree living room. Thus, strive to keep temperatures on the cool side. Coolness is particularly desirable for plants that bear fragrant flowers. I removed the storm sashes from a few of my windows in order to provide my heliotrope, primroses, freesia (above) and other aromatic growers with the chilly conditions they prefer. Tropical plants, too, prefer a cool, humid room to one that is hot and dry. To keep all of my plants happy, I never raise my thermostat higher than 65 degrees, and I always lower it five or ten degrees at night.
3. Provide humidity. When the tips and/or edges of leaves turn brown, or when leaves turn yellow and drop, or when flower buds fall off before opening, a too-dry atmosphere is usually to blame. (Dry air is also an invitation to the red spider, who will weave tiny webs around leaves.) Most plants enjoy relative humidity in the 40 to 60 percent range, a definite challenge in winter. For when the furnace is running, humidity plummets. If you suffer from dry skin and a scratchy throat during the heating season, just imagine how miserable your plants are! (Air-conditioning also produces a dry environment.)
To boost humidity, set your pots on a pebble-filled tray. When plants are watered, surplus will drip into the tray, and produce humidity as it evaporates. More water, poured daily into the tray, will insure a steady source of evaporation. The pots, of course, must rest on the pebbles, above the level of water. Pebble-filled saucers are a useful alternative to trays.
4. Water only when necessary. Monday may be laundry day, but it is impossible to schedule such a routine for watering your houseplants. Daily inspection is the best policy. When a clay pot appears light in color, or when the top soil approaches dryness, go ahead and water. Make a thorough job of it, too, by completely soaking the root mass until water drips from the drainage hole. Then, unless the plant rests on a humidifying bed of pebbles, immediately empty the saucer. Few plants beyond the primrose and cyclamen will tolerate standing water at their roots.
5. Remember to feed. I give my plants a small amount of food with every watering. Those grown in windows receive a quarter-teaspoon of food, dissolved in a gallon of room-temperature water. Plants that grow beneath fluorescents in my kitchen and study receive more food, because they work such long hours each day regardless of the season or weather. I give them a half-teaspoon of formula per gallon of water.
6. Freshen the air. A daily dose of fresh, humid air will greatly increase a plant’s resistance to disease. During the mild weeks of late spring and early fall, provide ventilation by opening every window in your home. In winter, open a window in an adjoining room for a few minutes each day. This will permit the air to warm as it travels to your plants.
7. Loosen the top soil. Over time, regular top-watering causes the surface soil in a pot to become so hard and compacted that air can not pass through. This is particularly dangerous for plants grown in nonporous plastic or glazed pots. Once each month, loosen the top soil with a kitchen fork. Poke about gently, however, to avoid damaging roots that may lie near the surface.
You might want to print out this post, and tape it to your refrigerator. Then, if your petunia peters out, or your heliotrope looks haggard, you can easily review these seven essentials for health and beauty. In any event, let me know how your houseplants are doing by posting a comment below.
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Donna says
Great tips, and that mantra is certainly worth repeating! And what a beautiful window! Is this in your house?
Kevin Lee Jacobs says
Donna – thanks. The window garden pictured above is indeed in my house, and what a pleasant vista it provides during the long, bitterly-cold months of winter!
Andrew Thompson says
I've never had luck with any ferns – they always wither and brown, no matter how much I mist them with water. Any tips?
Kevin Lee Jacobs says
Andrew – Ferns love humidity, but misting is not the answer. The effect is too temporary. Better to place the plants on a pebble-and-water filled tray. There, humidity will be constant.
Coolness helps, too. Plants are far more sensitive to heat and dryness than people are.
Gardenlady says
The window garden is lovely, as are the plants, including the blue hydrangea. Is this a southern exposure?
Eric says
The picture of your window garden is really inspiring! What are the vines in the center window, and also the one on the right? Philodendron?
Joan says
I needed this, Kevin. It's so easy to drift by my plants ignoring them for days, then suddenly realize they need EVERYTHING. I'll print your advice, get a few new plants for my east bay window exposure (what do you recommend–easy care and flowers?), and start a whole new regime.
One more question: what do I do about my husband who will be tending the plants while I travel in Maine for l0 days?
Kevin Lee Jacobs says
Gardenlady – the garden pictured above is in a window that faces south-east.
Eric – You are correct: the vine beneath the center window is the small-leaved philodendron (P. Scandens); at right is a hoya vine. The hoya grew so much that it now frames a window in the guest-room.
Kevin Lee Jacobs says
Joan – It's SO easy to ignore houseplants during summer, unless you move them to a shady place outdoors, and preferably near a hose!
There are many flowering plants suitable for an east window, and I'll soon publish a post that concerns this very topic. In the meantime, three “easies” come to mind: Begonia semperflorens (the common wax begonia), Saintpaulia ionantha (African violet), and Osmanthus fragrans (Sweet Olive).
Concerning your travel plans…Here are two suggestions for insuring the plants survive for a couple of weeks: 1) Before you leave, water the plants well. Then leave a watering can, already filled with a dilute fertilizing solution, near the plants. Call your husband every other day, and ask him to check the top soil. If it appears slightly dry, ask him to water the plants. Or…
Water the plants well. Then place a clear plastic bag around each. Not the most attractive thing in the world, I'll admit, but the plants will revel in the humidity the bags afford, and not require a drop of water for at least 10 days!
Carol says
Personally, I would NEVER leave my husband in charge of my houseplants, especially during sports season! Just sayin'.
Collin says
Kevin, your window garden is a magnificent work of art. Bravo!
Mary Unurh says
Love this post because while I feel pretty accomplished outside, I struggle inside. I forget to water, then overwater, temperature and humidity where too challenging ('tight' newer house, dry hot summer air, cold HUMID winter air…) I hate dealing with the pesticides needed for mites, scales, etc (though neem oil has been a blessing), and so for a while I gave up on anything but the hardiest. Then I had a couple of little mini me's and I got even more distracted! Lol. I have learned some valuable lessons from this though….not every plant can grow in your house but you can grow some beautiful things well everywhere. Start with what you are good at, add what does well indoors in your area/climate, branch out when and if you have more time. For me my standbys are clivias, cymbidiums, Christmas/Easter cactus, a ficus, African violets, a big aloe, and a mother in laws tongue (old fashioned I know but I love the vertical contrast with other softer things) In my kitchen window I have a smallish Boston fern and tillandsias because I can pay attention to them there (and my light shelf is in my pantry near by so I can also attend to it/ SEE it.) And on my island I rotate a display of orchids I keep under the lights when not in bloom (Paphilopedilums, Phalenopsis, etc), fresh flowers, forced branches, and collected objects I love. I am working on a species cactus orchid start my mother brought a piece of from Greece, and I am a nut for planted aquariums so I have a 37gallon in progress ( which i recently added mangrove seedlings to …)
Kevin Lee Jacobs says
Mary – Glad you found the article helpful. Yes, having plants in the room you visit most makes daily inspection easy.
Anyway, seems like you have some fascinating plants in your collection. How cool are tillandsias, or Air Plants? I don't have any, but I've seen them displayed in all kinds of fascinating ways. And your 37 gal. aquarium (compared to my 10-gallon number) should hold an entire grove of mangrove!
Sonja says
This bad boy has been blooming since late October … I haven't done a thing to it except put it in the kitchen window where it's remained since it came home … Is it ever gonna stop and what to do next?
Sonja says
It's a poinsettia but I can't figure how to post it here … Check my pic Kevin as I will need advice on how to keep this one … TYVM
Kevin Lee Jacobs says
Sonja – Please send the picture of your poinsettia to [email protected].
sue says
Love the windows they are so beautiful. Would love to do this we have a big bay and a window just like thesmaller one. My biggest problem is we live on a highway and would need privacy any idea's for afterdark.? Would it be to cold for plants with curtain or shade over them in winter?
Kevin Lee Jacobs says
Sue – nice to meet you. You can absolutely draw a curtain and thus enclose the plants in cold during winter evenings. I do just that for the big window garden in my music room, which is also outfitted with glass shelves.
Fragrant plants — Hyacinths, Meyer lemon, African gardenia and Sweet Olive — to name just four — will especially appreciate the increased humidity the nighttime curtain-enclosure will afford. You can find more cold-lovers by clicking “houseplants” on the right-hand side of this website.
If you need more tips on creating such a window garden, by all means let me know. I'm happy to help.