Alyssum Grow Guide – Sweet Fragrance and Carpet Blooms for South African Gardens

Alyssum is one of the easiest and most rewarding annuals to grow. With its masses of dainty flowers and honey-like fragrance, it’s perfect for borders, pots, rockeries, hanging baskets, and even as a living mulch between veggies. This guide will help you sow and grow Alyssum successfully across South Africa.

🌍 South African Growing Conditions by Region

Western Cape (Mediterranean)

• Best grown in autumn to spring.

• Mild, wet winters suit germination, but protect from heavy rain.

• Summer can be too hot/dry – grow in semi-shade if sowing then.

Eastern Cape (coastal vs inland)

• Coastal: Sow almost year-round, but avoid peak summer heat.

• Inland: Frost-prone, so best in spring and autumn.

Highveld – Gauteng, Free State

• Sow in spring and early autumn.

• Protect seedlings from late frost.

• Summer heat is fine if given regular water and some afternoon shade.

KwaZulu-Natal Coast (subtropical)

• Can be sown almost all year round, except peak midsummer heat/humidity.

• Prefers morning sun, afternoon shade in very hot spots.

KwaZulu-Natal Midlands

• Cooler, misty climate – sow in spring and summer.

• Protect from frost in winter.

Mpumalanga / Lowveld (semi-tropical)

• Sow in autumn, winter, and spring.

• Use shade netting to protect from scorching summer heat.

📅 Growing Calendar – When to Sow

• Western Cape: Feb–May, Aug–Oct

• Eastern Cape: Feb–Jun, Aug–Oct

• Highveld: Aug–Oct, Feb–Apr

• KZN Coast: Feb–Jun, Aug–Oct (avoid Jan humidity)

• KZN Midlands: Sep–Jan

• Lowveld: Mar–May, Jul–Sep

👉 Direct sow in the garden for quick cover or start in trays for more control.

🌱 Sowing Method

• Direct Sowing: Sprinkle thinly on prepared, moist soil. Lightly cover.

• Seed Trays / Jiffy Plugs: Recommended for better control. Sow 3–4 seeds per cell. Transplant as small clumps.

• Pots & Hanging Baskets: Alyssum thrives in containers – perfect for patios.

💡 Tip: Alyssum seeds are tiny – mix with dry sand for even sowing.

📏 Planting Depth & Growing Media

• Depth: 0.1 cm / 1mm (just lightly covered).

• Media options:

  1. Fine seedling mix.

  2. Compost + river sand or perlite (50:50).

  3. Jiffy plugs for neat clumps.

🌿 Growing Conditions

• Soil: Well-drained, light soil enriched with compost.

• Light: Full sun to semi-shade. Afternoon shade helps in very hot regions.

• Temperature: Germinates best at 10–20°C.

• Watering: Keep moist but never waterlogged. Allow surface to dry slightly before watering again.

• Germination: 14–28 days.

• Transplanting: At 5–7 cm tall, plant in clumps, spacing 10–15 cm apart.

🍃 Feeding & Fertilising

• Seed Stage: No fertiliser needed in sterile mix.

• Seedling Stage: Once 2–3 true leaves show, feed weekly with diluted seaweed extract or compost tea.

• Mature Plants: Use a slow-release fertiliser or liquid feed every 2–3 weeks to keep blooms going.

  • Good choices: bone meal in soil, compost mulch, or an organic flower booster.

✅ Do’s & Don’ts

Do:

• Sow shallow – just cover seeds.

• Thin seedlings or transplant clumps to prevent overcrowding.

• Trim back faded flowers for more blooms.

• Mulch around plants to retain moisture and suppress weeds.

Don’t:

• Overwater – roots rot easily in soggy soil.

• Sow in peak heat (unless shaded).

• Separate seedlings too roughly – plant clumps instead.

🌟 Tips & Tricks

• Companion Planting: Great with roses, pansies, violas, and edging veggie beds (attracts pollinators).

• Frost Protection: On the Highveld and Midlands, cover with frost cloth in early spring.

• Summer Shade: In the Lowveld, use 30% shade netting to reduce stress.

• Continuous Colour: Trim after first flush of flowers – new shoots bring fresh blooms.

🌸 The Joy of Growing Alyssum

Alyssum is proof that big joy can come in small packages. With little effort, you’ll enjoy carpets of colour, sweet fragrance, and a garden buzzing with bees and butterflies. Perfect for beginners and a delight for seasoned gardeners – Alyssum is a must-have in every South African garden.