Marsh Mallow

250 Seeds

Seeding Marsh Mallow (Althaea officinalis) is a great choice if you’re interested in a beautiful medicinal herb that’s also attractive in the garden. This hardy perennial produces soft, velvety leaves and pale pink to white hibiscus-like flowers, and it thrives in moist soil—hence its common name.

Here's how to successfully grow Marsh Mallow from seed:

🌱 Marsh Mallow – Seeding Guide

🌿 Quick Facts

• Botanical name: Althaea officinalis

• Plant type: Perennial herb

• Height: 3–5 ft (90–150 cm)

• Flower color: Pale pink to white

• Bloom time: Midsummer to early fall

• Hardiness: Zones 3–9

• Soil preference: Moist, well-draining, slightly alkaline

📅 When to Sow

• Indoors: 6–8 weeks before the last frost

• Outdoors: Early spring (after frost) or fall (for natural stratification)

🌡️ Cold Stratification (Recommended for Best Germination)

1. Mix seeds with moist sand or vermiculite.

2. Place in a sealed bag or container.

3. Refrigerate for 2–4 weeks.

4. After chilling, sow as below.

Note: Some seeds will germinate without stratification, but rates improve significantly with it.

🌱 Sowing Instructions (Indoors or Outdoors)

1. Sow depth: ¼ inch (6 mm)

2. Soil: Moist, rich, well-drained soil

3. Germination temp: ~65–70°F (18–21°C)

4. Germination time: 10–21 days

5. Light: Needs full sun to part shade

🌞 Transplanting Outdoors

• Timing: After last frost date and when seedlings have 2–3 true leaves

• Spacing: 18–24 inches (45–60 cm) apart

• Location: Sunny spot with moist soil (ideal near a pond, rain garden, or low spot)

💧 Care Tips

• Watering: Prefers consistently moist soil—does not like to dry out

• Mulching: Helps retain soil moisture and keeps roots cool

• Fertilizing: Generally not needed in rich soil; light compost in spring is enough

• Cutting back: In fall or early spring to encourage strong new growth

🌸 Companion Plants

• Grows well with valerian, echinacea, comfrey, and mint in a medicinal herb garden

🌿 Medicinal Use (Traditional)

• Roots and leaves have been used for soothing sore throats, coughs, and skin inflammation

• Only harvest from second-year or older plants

Note: Always consult a healthcare provider before using herbs medicinally.