Florist's cyclamen

Identification and origin

Cyclamen persicum belongs to the Primulaceae. Despite its name, it does not come from Persia: it grows wild from Algeria and Tunisia to Greece, Crete, the East Aegean islands, Turkey, Cyprus, Lebanon, Syria and Palestine. There it grows in pine forests, oak thickets and on rocky slopes, in a climate of hot, dry summers and cool, wet winters. Introduced to Western Europe in the 17th century, it is now grown and sold by florists all over the world. The name Cyclamen comes from the Greek kyklos, “circle,” a reference to the rounded tuber.

The plant forms a rounded mound 6–16 in tall depending on the type: miniatures stay under 6 in, while standard sizes reach about 12 in. The heart-shaped, dark green leaves are often marbled with silver. Each flower, about 2 in across, is borne singly on a stalk that rises straight from the tuber; its swept-back petals give it the look of a butterfly. Colors range from white to pink, red, magenta and lavender, and forms can be single, double, fringed or ruffled. The wild species is fragrant, but many cultivated varieties are not. Bees pollinate the flowers; the fruit, a five-chambered capsule, releases sticky, sugary seeds that attract ants.

When buying, choose a plant with dark green foliage that is just starting to bloom: lift the leaves to check that plenty of buds are still waiting to open.

Light

Cyclamen needs bright light, but not harsh direct sun. An east-facing window works well, as does a spot set back from a south-facing window. Sun that is too strong scorches the leaves. On the other hand, the low light common in homes produces a weak plant with long leaf stalks and smaller, paler flowers. To prepare for another bloom, when young leaves reappear in late summer, give it the brightest light possible.

Watering

Cyclamen dislikes both soggy and dry soil: either one turns the leaves yellow. Touch the surface: water when it feels dry and wait if it is still damp. Check every day: near a radiator or heater, the root ball dries out very quickly.

The tuber sits partly above the soil: never wet the center of the plant, which would rot. Watering from below is best: set the pot in a shallow bowl of room-temperature water for about 15 minutes, lift it out as soon as the surface starts to moisten, then let it drain. Never leave water standing in the saucer. Otherwise, pour the water right at the rim of the pot.

The air should stay fairly humid, above 50% relative humidity if possible: a tray of moist pebbles or a humidifier helps the flowers last longer.

Potting mix

Use a rich, well-drained potting mix, slightly acidic to neutral, in a pot with drainage holes. While the plant is blooming, apply a diluted liquid fertilizer every two weeks. After the summer rest, resume feeding when new growth starts, with a high-phosphorus fertilizer.

Temperature

This is the key to success: cyclamen loves cool conditions. Aim for 55–64 °F during the day and 50–55 °F at night. Above 70 °F, buds stop developing and the plant declines quickly; warm, dry rooms explain most short-lived cyclamens. Keep it away from radiators and heating vents.

During the summer rest, keep it at about 45–50 °F in the shade, and do not expose it to anything colder: the plant is frost tender. In the ground it can only be grown in USDA zones 9a to 11b.

Repotting

Repot at the end of the rest period, just before new growth begins, into fresh potting mix. Set the tuber so that its top sits slightly above the surface: it should be buried about halfway. Then return the plant to bright light in a cool room and water lightly until it has grown enough leaves.

Pruning

No real pruning is needed. Remove faded flowers as soon as they droop: grasp the stem firmly and pull it away completely from the tuber. This encourages more flowers. Also cut off any yellowed leaves.

Propagation

Professional growers propagate cyclamen only from seed. The seed must be fresh; germination takes 20 to 30 days and is erratic. Sow in seed-starting mix with added grit, cover with a thin layer of sifted mix, enclose the pot in a clear plastic bag and keep it at no less than 61 °F in light shade. It then takes 9 to 15 months to produce a flowering plant, even in a greenhouse.

Dividing the tuber is not recommended: it has few growing points and, once cut, it easily dries out or rots.

Common problems

• Yellowing leaves: too little light, a room that is too warm, too much or too little water; or simply the start of dormancy in late spring.
• Plant suddenly collapses: mix kept too wet; watch bottom watering closely.
• Buds fail to open: temperature too high.
• Scorched leaves: sun too strong.
• Tuber rot: overwatering or water poured onto the center of the plant.
• Gray fuzz on flowers and leaves: gray mold.
• Pests: aphids, mealybugs, spider mites and thrips can be treated with insecticidal soap. Cyclamen mites, favored by warm, dry air, are very hard to control: discard an infested plant. Under glass, also watch for black vine weevil larvae in the mix.

A single symptom can have several causes: always check temperature, light and soil moisture before drawing conclusions.

Toxicity

Cyclamen is toxic to dogs, cats and horses. It contains triterpenoid saponins, mainly in the tuber. Ingestion causes drooling, vomiting and diarrhea; eating a large amount of tuber can lead to heart rhythm abnormalities, seizures and death.

In people, toxicity is low and poisonings are rare because the plant tastes unpleasant; ingestion can cause vomiting and diarrhea, and handling the plant sometimes irritates the skin. Keep the pot out of reach of pets and children and, in case of ingestion, contact a veterinarian or a poison control center.