Lavatera arborea

Growing in Pots, Balconies & Indoors

Tree mallow (Lavatera arborea) is a fast, short-lived, sun-loving mallow that the grower marks as not a houseplant but confirms grows well in containers. In a pot on a sunny patio or balcony it flowers freely for its brief life.

Quick Details

• Container Size: A medium to large pot (mature size 0.5-2 m)
• Indoor Suitability: Not a houseplant – needs full sun to flower
• Best Spot: Full sun to part shade
• Soil & Drainage: Free-draining, fertile mix
• Watering in Pots: Moderate to generous; let the surface dry between waterings

Indoors & On the Windowsill

• Not a houseplant: Marked No – it needs full sun to flower and grows too tall and soft for indoor life.
• Windowsill: A very sunny sill might raise a young plant, but it soon outgrows a sill and flowers poorly in weak light.

On a Balcony or Patio

• Light & shelter: The sunniest spot; stake it and shelter from wind, as the stems are soft and top-heavy.
• Watering & heat: Water moderately to generously in growth; pots dry fast in summer heat.
• Overwintering: Short-lived (often biennial) – expect to replace plants; protect pots from hard frost.

Choosing the Pot, Soil & Long-Term Care

• Pot & drainage: A medium-to-large pot with strong drainage holes; skip a standing-water saucer to avoid root rot. Terracotta breathes and dries fast, while glazed or plastic holds moisture longer.
• Potting mix: A well-aerated, organic-rich mix – peat or coir blended with perlite or vermiculite for free drainage.
• Feeding: Potted plants run their soil down fast as nutrients leach out, so feed more often than plants in open ground during active growth.
• Repotting: Refresh the mix or pot up about every two years; on established plants, lightly prune the root ball and top growth to keep them balanced.

Bloom & Flower Guide

Quick Details

• Bloom Season: Spring, summer and into autumn
• Flower Appearance: Saucer-shaped, five-petalled purple flowers with a dark centre; in some cultivars the petals merge at the base
• Edibility: Grown as an ornamental hedge; the flowers are not the eaten part of this mallow

Detailed Blooming Overview

Tree mallow flowers generously over a long season, from spring right through to autumn. The open, saucer-shaped purple flowers, each set off by a darker eye, are carried up the tall stems and are a great favourite with bees. It is a fast, free-flowering shrub that often seeds itself around.

Flower Characteristics

• Purple, five-petalled, saucer-shaped flowers with a dark centre.
• In some cultivars the petals fuse at the base.

Bloom Care & Thinning

• Pollination: Bees work the open flowers freely.
• Managing the bloom: Trimming spent flowering stems tidies the plant and can limit its prolific self-seeding.