When to plant Verbena in Subtropical Australia

Subtropical zone — applies to Brisbane, Gold Coast, Sunshine Coast, Coffs Harbour, Lismore and similar areas. Growing elsewhere? Temperate · Cool · Tropical · Arid.

Sow verbena direct across a long window from February to September, scattering seed where the plants are to flower. Germination is slow and can be uneven, taking 10–20 days, with plants flowering in around 70 days. Sow 6 mm deep and thin to 25–30 cm apart in rows 30 cm apart. Verbena loves warmth and sun once established, making it a dependable, long-flowering filler for Brisbane and Gold Coast gardens. The generous sowing window means you can slot it in through much of the year, though autumn and early spring give the most reliable germination.

Sowing calendar — subtropical zone

Green months are your sowing window: February to September.

Growing notes

Verbena is a sun-loving, heat-tolerant flower, which makes it a good fit for subtropical gardens once it is up and growing. The long February to September window reflects this adaptability, though germination is the tricky stage and does best in the milder shoulders of the year rather than the peak wet.

Slow, patchy germination is the main frustration. Verbena seed likes warmth but resents wet, so sow into a free-draining bed, keep it just moist rather than soaked, and be patient across the full 10–20 day window. Old seed germinates poorly, so use fresh stock.

Once established, the bigger risk is powdery mildew, which appears as white bloom on leaves in humid, still conditions. Space plants 25–30 cm apart for airflow, water at the base early in the day, and give full sun, which verbena relishes. Avoid overhead watering that leaves foliage wet overnight. Deadhead spent flower clusters to keep the plant blooming for months rather than setting seed and stalling. In Coffs Harbour and the Sunshine Coast, verbena copes with heat and humidity better than most cottage flowers, so it earns its place in a warm, exposed bed where fussier plants struggle.

Verbena at a glance

Common questions

When should I sow verbena in the subtropics?

You have a long window from February to September, but autumn and early spring give the most reliable germination. Avoid sowing into the wettest, most humid weeks, when seed is prone to rotting. Once up, verbena flowers within about 70 days.

Why is my verbena seed slow to germinate?

Verbena naturally germinates slowly and unevenly over 10–20 days. Wet, cold soil and old seed both worsen this. Sow fresh seed into a warm, free-draining bed and keep it just moist while you wait.

Does verbena cope with subtropical humidity?

Verbena handles heat and humidity better than most cottage flowers, which is why it suits Brisbane gardens. Its main weakness is powdery mildew in still, damp conditions, so give it full sun and good spacing. Water at the base to keep foliage dry.

How do I keep verbena flowering longer?

Deadhead spent flower clusters regularly to stop the plant setting seed and stalling. Give it full sun and a light feed through the growing season. With this care verbena can flower for many months in a warm bed.

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