How to Sow and Grow Nasturtiums

Nasturtiums are bright, cheerful flowers that not only add vibrant colour to your garden but also serve practical purposes like attracting beneficial insects and even offering edible flowers and leaves. Whether you’re an experienced gardener or a beginner, nasturtiums are easy to grow, making them a favourite choice for garden beds, borders, hanging baskets, and containers.

Nasturtium Milk Maid

Why Grow Nasturtiums

Here’s why nasturtiums are such a great choice for your garden:

• Easy to Grow: They require little maintenance and tolerate poor soil, making them perfect for beginners.
• Vibrant Blooms: Available in a variety of warm colours like red, orange, and yellow, they brighten up any garden.
• Edible Flowers and Leaves: Both have a slightly peppery flavour, adding zest to salads, sandwiches, or as garnishes.
• Beneficial Companion Plant: Nasturtiums attract pollinators like bees and butterflies, while also acting as a trap crop for aphids, protecting nearby vegetables.

When to Plant

• Outdoors: Nasturtiums thrive in warm weather, so sow the seeds outside after the last frost date in your area, typically in late spring. Soil temperatures should be at least 13°C for successful germination.
• Indoors: If you prefer to start them early, sow seeds indoors 4-6 weeks before the last frost and transplant them once the weather warms up.

Nasturtium Mahogany Jewel

Preparing the Soil

• Soil Type: Nasturtiums actually prefer poorer, well-drained soil. Fertile soil encourages leafy growth but reduces flowering.
• Position: Choose a spot that gets full sun to partial shade. Full sun encourages more flowers, though they will tolerate light shade.

Sowing the Seeds

• Direct Sowing: In your garden bed or container, plant the seeds about 2.5 cm deep and 25-30 cm apart.
• Watering: Water the seeds thoroughly after planting and keep the soil moist but not soggy during germination.
• Germination: Nasturtium seeds typically germinate in 7-10 days, depending on temperature and soil conditions.

Indoor Sowing

• Use biodegradable pots or seed trays, filling them with seed-starting mix.
• Plant one or two seeds per pot about 4 cm deep.
• Keep the pots in a warm, sunny spot and water lightly to keep the soil moist.
• Once the seedlings are 8-12 cm tall, and the weather is consistently warm, they can be transplanted into the garden.

Nasturtium Purple Emperor

Care and Maintenance 

Once your nasturtiums are established, they need minimal care. Here’s how to keep them blooming and healthy throughout the season:

Watering

• While nasturtiums are relatively drought-tolerant, regular watering will encourage better blooming. Water them moderately, aiming to keep the soil slightly moist but not waterlogged.
• Be careful not to overwater, as overly wet soil can lead to root rot.

Deadheading

• Regularly remove spent blooms to encourage more flowers. Deadheading also keeps the plants looking tidy.
• If you’re growing nasturtiums for seeds or want them to self-seed, leave a few flowers to develop seed pods.

Pest Control

• Aphids: Nasturtiums are particularly attractive to aphids, which is beneficial if you’re using them as a trap crop for other plants. However, if aphids become too invasive, a strong spray of water can help dislodge them.
• Caterpillars: These insects also enjoy nasturtium leaves but can be easily picked off by hand if they become problematic.

Nasturtium Bloody Mary

Harvesting and Using Nasturtiums

One of the best parts of growing nasturtiums is that you can use the flowers and leaves in the kitchen.

• Flowers: The vibrant blossoms have a peppery flavour and are great for garnishing salads, soups, and even desserts.
• Leaves: The leaves add a fresh, spicy taste to salads and sandwiches.
• Seeds: You can also collect seeds from the plants. Once the flowers fade, the seeds will develop in pods. Let them dry and store them for planting next season.

 Nasturtium Peach Melba

Nasturtium Peach Melba

Growing nasturtiums is a rewarding and low-maintenance gardening project that offers colour, charm, and practicality to any outdoor space. Their bright blooms and edible qualities make them a standout in flower beds, containers, and even vegetable gardens. With just a little care and attention, you’ll have a garden full of vibrant, cheerful nasturtiums to enjoy all summer long. Happy growing!

Video – How to Sow and Grow Nasturtiums