Zinnias are the shining stars of the summer garden, bursting with vibrant colour and charm. With their incredible range of flower shapes – single, semi-double, and fully double blooms – they offer endless variety. Sizes range from petite blooms perfect for pots to bold statement flowers that light up garden beds. And the colours… zinnias come in every shade you can imagine, from fiery oranges and sunny yellows to soft pinks and deep reds.
In the garden, they’re perfect for creating cheerful borders or massed displays, and they also thrive in containers for brightening up patios or balconies. Best of all, zinnias often self-seed, popping up as welcomed surprises next season. If you need an instant colour boost right now, then zinnias are your summer go-to. Check your local garden centre for potted zinnias and get planting. These low-maintenance beauties will reward you with a flurry of joyful blooms as the warm weather continues.
Everything you need to know on growing Zinnias
Zinnias are one of the easiest and most rewarding flowers to grow, especially in Australia’s warm climate. Here’s how to grow them successfully:
Zinnias are one of the easiest and most rewarding flowers to grow, especially in Australia’s warm climate. Here’s how to grow them successfully:
Choose the right variety
Zinnias come in different heights and flower sizes. Some popular varieties include:
- Zinnia elegans – Tall and classic with large blooms.
- Zinnia angustifolia – Compact and great for borders.
- Zahara & Profusion series – Heat-tolerant and disease-resistant.
Best time to plant
- In warm climates (e.g., Queensland, Northern Australia) – Plant in autumn, winter, and early spring
- In cooler climates (e.g., southern Australia) – Plant in spring and summer after the last frost.
Choosing a location
- Full sun (at least 6 hours per day).
- Well-drained, moderately fertile soil.
Sowing seeds
- Directly sow seeds into the garden or start in seed trays.
- Space 20-30 cm apart for airflow (helps prevent mildew). Cover lightly with soil and keep moist until germination (5-7 days).
Watering & care
- Water deeply but infrequently (avoid wetting leaves to prevent mildew).
- Deadhead spent flowers to encourage more blooms.
- Apply a light liquid fertiliser every 2-3 weeks.
Pest & disease management
- Watch for powdery mildew (improve airflow, avoid overhead watering).
- Control aphids and caterpillars with insecticidal soap or neem oil.
Enjoy the blooms!
Zinnias bloom within 6-8 weeks of planting and continue flowering until frost (or year-round in warm areas). They’re excellent for cut flowers and attracting pollinators!
Best companion plants for zinnias
Vegetables
Zinnias help attract pollinators and beneficial insects, making them perfect for vegetable gardens.
- Tomatoes– Zinnias attract bees, improving tomato pollination and yield.
- Cucumbers– Their bright blooms lure pollinators needed for cucumber fruiting.
- Capsicums & Chillies – Encourage natural pest control by attracting ladybugs and hoverflies.
- Beans & Peas – Fix nitrogen in the soil, benefiting zinnias.
Herbs
Zinnias work well with herbs that repel pests and attract pollinators.
- Dill & Fennel – Attract beneficial insects like ladybugs and lacewings.
- Basil– Improves pollination for both plants and repels pests.
- Rosemary & Thyme – Help deter aphids and caterpillars.
Flowers
Pairing zinnias with other flowers boosts biodiversity and extends blooming seasons.
- Marigolds– Both repel nematodes and pests.
- Cosmos – Another pollinator magnet that thrives with zinnias.
- Lavender – Attracts bees and deters pests.
- Sunflowers– Adds height and creates a stunning summer display.
Plants to avoid
- Potatoes – Zinnias can attract leafhoppers that spread disease to potatoes.
- Squash & Pumpkins – Too much competition for pollinators can reduce fruit set.
