How to grow alstroemeria
Overview
Alstroemeria aurea is a tuberous herbaceous perennial grown for its showy, long-lasting flowers and attractive foliage. It is a popular cut flower that thrives in full sun and well-drained soil, providing continuous colour from late spring through autumn.
Varieties
- Alstroemeria 'Princess' series — Compact, dwarf varieties ideal for pots and borders, with a wide colour range.
- Alstroemeria 'Indian Summer' — Vigorous, tall-growing with orange-red flowers; excellent for cut flower production.
- Alstroemeria 'Sweet Laura' — Fragrant, yellow-orange flowers; one of the few scented cultivars.
Soil Preparation
Alstroemeria prefers slightly acidic to neutral soil (pH 6.0-7.0) with good drainage. Enrich with well-rotted compost or manure before planting. Avoid heavy clay soils that stay wet; improve drainage with raised beds or coarse sand.
Growing Guide
Plant alstroemeria in full sun with well-drained soil enriched with organic matter. Space tubers 30-40 cm apart and 10-15 cm deep, with the crown just below the surface. Water regularly during active growth, allowing the soil to dry slightly between waterings. Mulch to keep roots cool and suppress weeds. Divide crowded clumps every 2-3 years in late autumn to maintain vigour and prevent overcrowding.
Sowing
Alstroemeria is typically grown from tubers or divisions, not from seed. If sowing seed, surface-sow in a seed tray with light covering of vermiculite, keep at 15-20°C, and expect germination in 3-6 weeks. Seedlings take 2-3 years to flower.
Care
Feed with a balanced slow-release fertiliser in early spring and again after the main flowering flush. Cut back spent flower stems to the base to encourage reblooming. Divide crowded clumps every 2-3 years in late autumn to maintain vigour and prevent root congestion.
Companion Planting
Alstroemeria pairs well with roses, lavender, and salvia, which share similar sun and water needs. Avoid planting near vigorous groundcovers like mint or creeping Jenny that may compete for root space.
Common Pests & Risks
Slugs and snails can damage young shoots and foliage; control with iron-based pellets or beer traps. Aphids may appear on new growth; treat with a strong water spray or insecticidal soap. Spider mites can occur in dry conditions; increase humidity and use neem oil if needed.
Harvesting
Harvest alstroemeria stems when the first two flowers on a stem have opened, pulling the stem from the base rather than cutting. This encourages new growth from the crown. Stems last 7-10 days in a vase; remove lower leaves to prevent water fouling.
Troubleshooting
Yellowing leaves: overwatering or poor drainage; reduce watering and improve soil drainage. Stunted growth: root congestion from overcrowding; divide clumps every 2-3 years. Flower buds fail to open: aphid damage or insufficient light; check for pests and ensure full sun. Leaf spots: fungal disease from wet foliage; water at soil level and improve air circulation. Stems flopping: lack of support or over-fertilising; stake stems and reduce nitrogen.