Jasmine care: pink jasmine as a winter-flowering houseplant

Light

Clemson Extension says indoor jasmines need at least four hours of direct sunlight daily, or 14 to 16 hours of strong artificial light. A south window is the best match; by University of Illinois Extension measurements, the spot directly in front of a south window receives about 1,500 foot-candles, while a few feet back the level falls quickly. A west window works as a second choice, especially in winter when the sun is lower and reaches farther into the room.

Light is what builds next winter's flowers, so summer counts as much as winter. The RHS suggests moving tender jasmines outside to a warm, sheltered spot in summer, which gives far more light than any window. Ease the plant into full outdoor exposure over a week or two, as Illinois Extension recommends for houseplants moved outdoors, so leaves grown indoors do not scorch.

Water

The RHS gives the pattern plainly: houseplant jasmines need regular watering while in growth, and only very light watering in winter. During spring and summer, check the pot often and water thoroughly as soon as the surface feels dry, letting the excess drain away. A pot outdoors in summer, packed with roots and leaves, can dry out remarkably fast.

Winter is trickier because that is when buds form and open. Growth slows in cool rooms, so the mix stays damp longer, and heavy watering then leads to yellow leaves and weak roots. Yet a root ball that dries out completely while the plant is in bud often drops those buds. Aim for light, regular drinks that keep the mix just moist, and always empty the saucer.

Tap water is generally fine. If white crust builds up on the surface, the University of Illinois Extension recommends leaching the pot every four to six months with a large volume of plain water to wash out fertilizer salts.

Soil and pH

The RHS says jasmines need fertile, well-drained soil. For a pot, that translates into a good multipurpose or loam-based potting mix, with some compost for fertility and perlite if the mix feels heavy, in a container with drainage holes. Because the plant twines, give it something to climb: the wire hoop it is sold on works for a year or two, then a small trellis set into a larger pot lets you train new stems around it.

Humidity

None of our sources gives a humidity figure for pink jasmine, so we will not invent one. The University of Illinois Extension notes that most homes drop below 30 percent humidity in winter, which is when this plant is in bud and bloom. If the leaves look dull and dry in a heated room, set the pot on a tray of moist pebbles, with the pot above the water line, or group it with other plants. Keep the plant away from heat vents, which dry the air around it even further.

Temperature

Clemson Extension gives ideal indoor temperatures for semi-tropical jasmines of 68 to 72°F (20 to 22°C) by day and 50 to 55°F (10 to 13°C) at night. Those cool nights are the reason pink jasmine often blooms well in a chilly sunroom or by a cool window but sulks in a warm, evenly heated apartment. None of our sources spells out an exact chilling requirement for flower buds, but the cool night range is the closest guidance available.

The RHS is more cautious about cold. It says J. polyanthum needs to be kept consistently above 55°F (13°C) and should come indoors before night temperatures fall to 55 to 59°F. The two sources overlap at about 55°F, so a practical target is nights near 55°F, never colder than 50°F, and no icy drafts. Illinois Extension warns that cold window glass can damage foliage.

Fertilizer

To boost flowering, the RHS recommends feeding container jasmines with a high-potassium liquid fertilizer such as tomato feed, following the label. No source gives an interval for this species, so use the University of Illinois Extension houseplant guideline of once every one to three months between spring and early fall, while new stems grow. Those summer stems carry next year's flowers, so a well-fed, well-lit summer matters more than anything you do in winter. Ease off in late fall.

Work out the dose for your watering can with the fertilizer dilution calculator →

Repotting

Repot when roots grow through the drainage holes, the soil mass fills with roots or the plant wilts between normal waterings, the signs the University of Illinois Extension lists. Do it after flowering, in late spring, when the plant is actively growing and has time to settle before next winter's buds form. Move up one pot size, set the plant at the same depth, and transfer or replace its support at the same time so the twining stems are not torn.

• Roots circle the pot or grow through the drainage holes
• The plant wilts between normal waterings
• New leaves come in smaller than usual

Propagation

The RHS says tender jasmines root best from internodal softwood or semi-ripe cuttings taken in spring or summer. Internodal means you cut between two leaf joints rather than just below one. Take a few lengths of healthy, nonflowering stem, strip the lowest leaves, and insert them in a moist, free-draining cutting mix under a clear cover in bright, indirect light until new growth shows they have rooted.

Seed is rarely an option. The RHS notes that jasmines seldom produce berries in a cool climate, but if yours does, the seed can be sown; cuttings remain faster and give a plant identical to the parent.

Methods: Internodal softwood cuttings, Semi-ripe cuttings, Seed, if berries form · Best season: spring or summer.

Common problems

The RHS lists mealybugs and red spider mites as the sap-feeding pests that most often attack jasmine indoors, and urges regular checks because early outbreaks are much easier to control. Dry, warm rooms favor spider mites in particular. The other big complaint is a plant that grows but never blooms, which almost always traces back to too little light in summer or nights that stay too warm in fall and winter. A tangled, bare-stemmed plant needs pruning: the RHS recommends cutting flowered stems back to a strong side shoot and thinning weak ones.

Not sure which one it is? Try the plant problem diagnosis tool →

Is the jasmine toxic to cats and dogs?

The ASPCA lists true jasmine, Jasminum species, as non-toxic to dogs, cats and horses, so pink jasmine is a reasonable choice for a home with pets. The name causes confusion, though. Clemson Extension points out that star or Confederate jasmine is a Trachelospermum, not a true jasmine, and that Carolina jessamine (Gelsemium sempervirens) is a different plant again. More importantly, the ASPCA lists Cape jasmine (gardenia) as toxic, with mild vomiting, diarrhea and hives, and Paraguayan jasmine (Brunfelsia) as toxic, with tremors and seizures possible. Check the botanical name on the label before bringing any jasmine home.

Check any other plant against the ASPCA lists →