Polka dot plant

Polka dot plant: how do you recognise it?

Habit

Compact, branching plant, 30–40 cm high and 25–30 cm wide, with soft stems.

Leaves

Oval, 3–8 cm, soft, dark green with pink, red or white spots. The spots are strongest in good light.

Flowers

Small lilac-pink flowers in loose spikes; they are not conspicuous. Cut them off so that the plant stays compact.

Roots

Fine and shallow: it likes loose, moist compost.

Plants: March–April · Pruning: March–August

Why grow it?

• Colourful foliage all year round: a cheerful splash on the windowsill.
• Easy and fast-growing: a full plant within a few months.
• Fits in a small pot, a dish or a larger grouping of houseplants.
• Easy to propagate from cuttings, which root in a few weeks in water or compost.
• You can keep it small and compact by trimming it regularly.

Polka dot plant: where does it grow best?

• Light: plenty of light without strong sun, for example by an east-facing window or a little back from a south-facing one. In strong sun the leaves scorch; in a dark corner the spots fade.
• Temperature: 18–24 °C; not below about 15 °C and no draughts.
• Soil: loose, humus-rich potting compost, slightly acid to neutral.
• Humidity: it likes humid air. A bright bathroom or kitchen is fine; in dry air the leaf edges turn brown.

Light

Bright, out of direct sun

Potting soil

Multi-purpose compost or airy, humus-rich compost

Acidity

Acid or neutral

Watering

Moderately

Size

0.4 m tall, 0.3 m wide

Temperature

Minimum 15 °C

Goes well with

• Fittonia: Same warm, humid spot, with finely patterned leaves.
• Calathea: Striped leaves and the same humidity.
• Pilea: A compact plant with the same conditions.
• Ferns: Soft, green fronds next to the speckled leaves.

Polka dot plant: when and how to plant it?

Plant in March–April.

1. Repot in March–April, when the plant is growing actively again. Repot young plants every year.
2. Choose a pot of 10–14 cm with a hole in the bottom.
3. Use loose, humus-rich potting compost with a little perlite or sand for good drainage.
4. Set the plant at the same depth as before, top up and firm the compost lightly.
5. Water generously, let the excess drain away and put the plant in a bright spot.
6. Pinch back long shoots straight away so that it branches well.

Care

Water

Keep the compost evenly moist but not wet: water when the top centimetre is dry. In drought the leaves flop dramatically, but after a good watering it usually recovers within a few hours.

Feeding

From March to September, half-strength houseplant feed every 2 weeks; in winter at most once every 6–8 weeks.

Humidity

Mist now and then or stand the pot on a tray of damp pebbles, without the water touching the pot.

Pinching out

Pinch or cut out the shoot tips regularly and remove flower spikes: the plant stays compact and colourful.

Repotting

Fresh compost every spring, or replace old, bare plants with cuttings.

Tip: Pinch back the tips regularly and remove the flower spikes and it stays compact and colourful. Put it in a bright spot without strong sun so the spots stay vivid.

Polka dot plant: when to prune it?

Pruning months: March–August.

When: Throughout the growing season, from March to August inclusive. Do a harder prune in March.

How:

• Pinch or cut off the tip of each shoot regularly, just above a pair of leaves: this gives more branching.
• Remove flower spikes as soon as you see them.
• In March, cut old, bare or long plants back by about half; they shoot again within a few weeks.
• Use a sharp, clean knife or scissors.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Tip cuttings

From March to August: take tip cuttings of 8–10 cm with a few pairs of leaves, remove the lower leaves and stand them in a glass of water or moist compost. At about 20 °C they root in 1–3 weeks.

Seed

In March, sprinkle on moist compost without covering (it germinates in light) and keep moist at 20–24 °C. The seed germinates after a few weeks.

Polka dot plant: how does it get through the winter?

• Not hardy: keep it indoors all year round, at 15 °C minimum; avoid draughts and a cold windowsill.
• Put it in the brightest spot and water slightly less, but do not let the compost dry out.
• Little or no feeding. Keep the air humid when the heating is on.

Diseases and pests

• Long, bare shoots: Caused by too little light or too little pinching. Move it somewhere brighter and cut it back.
• Fading spots: Too little light: the plant turns greener. Move it somewhere brighter, but without strong sun.
• Drooping leaves: Usually drought: water and it recovers quickly. If the leaves stay limp while the compost is wet, it is root rot; repot in fresh, dry compost.
• Spider mite and mealybug: Fine webs or white cottony clumps, especially in dry air. Rinse the plant and increase the humidity.
• Brown leaf edges: Dry air, draughts or cold. Move it somewhere more humid and sheltered.

Through the year

• January: Move to the brightest spot; little water; no feeding.
• March: Cut back by half, repot and start feeding.
• April: Take cuttings. Pinch out regularly.
• May: Pinch out regularly; remove flower spikes.
• June: Water evenly; feed every 2 weeks.
• July: Protect from strong sun; pinch out.
• August: Water, feed and pinch out.
• September: Last feed. Take cuttings for winter.
• October: Move to the brightest spot; less water.
• December: Rest: warm, bright and little water.

Did you know?

• The name Hypoestes comes from Greek: hypo means ‘under’ and estia ‘house’, because the calyx is enclosed by small bracts.
• The spots are strongest in good light; in shade the leaves turn greener.
• Cuttings often root within a few weeks in a glass of water.