When to plant
Direct sow outdoors 2–3 weeks before last frost — seeds need cool soil to germinate. Also excellent as a fall crop. In mild climates, alyssum may self-seed and return every year without replanting.
Soil & site
Average to poor soil is fine — alyssum actually blooms better without rich soil. Good drainage is essential. Work in some compost for very clay-heavy soil. Slightly alkaline to neutral pH (6.5–7.5).
Feeding
Minimal feeding needed. Too much nitrogen causes lots of leaves with few flowers. A single light application of balanced fertilizer at planting is usually enough for the whole season.
Common problems
Aphids cluster on new growth — spray off with water. Downy mildew in humid conditions (improve air circulation, avoid overhead watering). Plants may pause blooming in extreme summer heat — cut back lightly and they'll rebound when temperatures cool.
When to harvest
Flowers are fully open and fragrant. Alyssum blooms continuously — you're harvesting both flowers and seeds. For seeds, let some flower clusters dry completely on the plant until the tiny pods turn brown and papery.
How to harvest
Snip individual stems or whole flower clusters for arrangements. For seeds, cut dry seed heads into a paper bag and shake to release the tiny seeds. Deadhead spent blooms regularly to keep the plant flowering all season.
Storage & use
Fresh flowers last a few days in water. Dried flowers can be used in sachets. Edible flowers add a mild honey-like flavor to salads and desserts. Seeds stored in a dry paper envelope keep viability for 2–3 years.
Useful for growing alyssum
A few things that make this one easier — chosen for this plant, not a generic list.
Some links on this page are affiliate links. If you buy through one we may earn a small commission, at no extra cost to you. As an Amazon Associate I earn from qualifying purchases. More.
Growing Alyssum this season?
Sprout Together plans your beds, tracks planting and harvest timing for your area, and keeps every guide in your pocket — free.
Get it on the App Store