Best Flowering Houseplants for Indoor Color

The plant did what it was grown to do, and then stopped.

Every flowering houseplant on a shop shelf was brought into bloom on purpose. A grower controlled the day length, the night temperature or both, on a schedule aimed at a date, and the plant arrived in your house at the end of that process rather than the start.

A living room reverses almost every condition involved. It holds one temperature day and night, and it carries light well past sunset, which is precisely what most flowering triggers are the absence of.

The display therefore ends and nothing replaces it. The leaves stay green, the plant grows, and the owner concludes they have done something wrong.

They have not. Getting a second flowering is a separate job from keeping the plant alive, and it is the job nobody is told about at the till.

Two things do nearly all the work, and neither of them is fertilizer.

The first is darkness. Some plants count the length of the night and will not set buds until the nights are long enough for long enough, which is why they flower in autumn and winter in the wild.

A holiday cactus is the clearest case. It needs at least 12 hours of continuous darkness for five to six weeks, flowering is best at 13 to 16 hours a night, and fourteen or more hours of unbroken darkness is required before bud set happens at all.

Timing that one is simple. Long nights start around the middle of September and run for at least six continuous weeks, with night temperatures of 55 to 60 degrees Fahrenheit through the period.

The second trigger is a temperature drop. A moth orchid needs nights 10 to 15 degrees cooler than its days, ideally 55 to 65 degrees against days of 70 to 80, held for six to eight weeks before a flower stalk appears.

Some plants have no seasonal trigger at all. An African violet flowers on light and steady mild temperatures of 60 to 75 degrees, which makes it the easiest of these to keep in bloom and the least dramatic to look after.

It takes far less light than anybody expects.

As little as two hours of interrupted lighting will inhibit flower bud set on a holiday cactus. Not two hours of sunshine, two hours of a lamp on a side table.

The list of culprits is longer than it looks. A reading lamp, a television, a hall light left on, a screen, and a street light coming through an uncurtained window all count against a plant sitting nearby.

The word that matters is continuous. A plant carried out to be admired for an hour in the evening has had its night broken, and the count starts again.

A spare bedroom nobody uses after dark is the easiest fix. A cupboard overnight works, and so does a cardboard box put over the plant each evening, provided it goes back into good light every day.

Then leave it alone for the full period. Six continuous weeks means six, and interrupting it in week four restarts the clock rather than shortening the wait.

The window decides what is possible before the trigger decides what repeats.

Bright indirect light is what nearly all of these want. A moth orchid, an African violet and a holiday cactus all flower on light that is generous without being direct, which in practice means near a bright window rather than in it.

Light level shows in the flowers as well as in the count. African violet blooms are brighter and last longer in high light with mild temperatures, and the same plant in a dim corner produces fewer, paler, shorter-lived flowers.

A north-facing window has its limits. It will keep a flowering houseplant alive and green for years, and it will not sustain repeated flowering on any of them.

Direct midday sun is the other extreme. Most of these plants carry thin leaves that scorch behind glass, and an orchid in a south window in July will burn before it flowers.

Bud drop is unopened buds falling from a plant that is otherwise perfectly healthy.

It is not the same as flowers finishing, and the difference shows on the soil surface. Finished flowers are brown and papery.

Dropped buds are plump, closed and still colored when they hit the compost.

A sudden change in conditions causes it, and buying the plant is the most common change there is. Light, temperature and humidity all shift at once between a greenhouse, a shop and a car, and buds are the first thing a plant lets go of when it is under pressure.

Draughts do the same thing to a plant that has not moved anywhere. A door that opens onto the street, a window left ajar, or a heating vent blowing across a shelf will all produce it in a plant that was perfectly happy the week before.

Letting the mix dry out hard while the buds are forming does it too. The plant sheds what it cannot support, and buds are the most expensive thing on it.

A plant in flower needs the water somewhere different from a plant that is not.

Water sitting on petals marks them and shortens the display, which is reason enough to keep the can away from the top of the plant.

The crown is the more serious problem. Plants that grow from a crown at soil level, African violets among them, rot at that point if water collects in it, and the rot goes downward into the plant rather than drying off.

Watering from below solves both. Stand the pot in a shallow saucer of water and let the mix draw up what it needs, which keeps the crown, the leaves and the flowers dry throughout.

Take the pot out once the surface of the mix is damp. Leaving it standing turns a good technique into the waterlogging described in the overwatering guide.

Check more often rather than watering more heavily. A plant in bloom is working harder and drinking faster, and the answer is frequency rather than volume.

Three of the plants on this page are on the ASPCA non-toxic list and three are not.

Phalaenopsis orchid, African violet and Christmas cactus are all listed as non-toxic to both cats and dogs, which makes them the straightforward choices for a home with animals.

Kalanchoe is the one people are most surprised by. It is toxic to both species through bufadienolides, causing vomiting, diarrhea and, rarely, an abnormal heart rhythm.

Peace lily and anthurium both carry insoluble calcium oxalate crystals, which cause painful swelling of the lips, mouth and tongue with heavy drooling. It hurts and it is rarely life threatening.

A peace lily is worth one clarification, since the name causes real fear. It is not a true lily, and it does not carry the kidney risk that a true lily carries for a cat.

The pet safe houseplants page sets out the full picture.