Nasturtium: Plant Care and Growing Guide

When to Plant Nasturtium Flowers?

• Seeds can be sown directly in the garden after your last spring frost date. Soil temperatures should ideally be between 55-65°F (12°-18°C).
• Start seeds indoors about 2-4 weeks before the last frost for earlier blooms.
• Plants germinate quickly, sprouting within 10-14 days and blooming in about 6 weeks.

Where to Plant Nasturtium Flowers?

• Nasturtium thrives in full sun (at least 6 hours of sunlight daily) in poor, well-drained soils. Some afternoon shade is appreciated in hot summer areas.
• Rich, fertile soils are not recommended as they yield more foliage but reduce flowering. Nasturtiums do better in soils of moderate to low fertility.
• They relishes cooler temperatures (in the 70sºF or 20sºC) and often sulks in extremely dry or humid conditions.
• Nasturtium is an excellent choice for beds and borders, edgings, as a ground cover, or in mass plantings. It is also suitable for kitchen gardens and containers and looks great in the cottage garden.
• Butterflies, bees, and other pollinators and beneficial insects are drawn to the flowers, making them valuable to the vegetable garden.
• In addition, Nasturtium can be used as a trap crop, trapping pests such as aphids and giving a more appealing and delicious meal than nearby vegetable crops.
• Nasturtium is a good companion plant for beans, broccoli, cabbage, cucumber, kale, melon, pumpkin, and radish.

How to Plant Nasturtium Flowers?

• When sowing directly into the garden, clear the area of weeds, then rake the surface to a fine, crumbly texture.
• Sow seeds about 1/2 inch deep (1 cm) and 10-12 inches apart (25-30 cm) in the garden.
• Water thoroughly after planting.
• Keep the soil moist until the seeds sprout, which should take about 10-14 days.

Caring for Nasturtium Flowers

Water and Moisture

• Water regularly throughout the growing season.
• Nasturtium is somewhat drought tolerant but will perform better in moist soil. If water-stressed, fewer flowers and leaves will be produced.

Fertilizer

• Nasturtium does not need any fertilizer.

Deadheading / Pruning

• Deadheading will promote more blooms.
• If the flowers are not deadheaded, the plants may self-sow.
• Nasturtium may need to be trimmed back occasionally over the growing season. This stimulates new growth and flower production.

Harvesting

• Only Nasturtium grown organically can be eaten. Never eat Nasturtium plant parts grown with pesticides or chemicals.
• Pick the edible leaves with or without their stalk when they are young and small.
• Clip flower buds with scissors right below the point where they join the stem.
• Clip the edible flowers with scissors when they are at their peak freshness – before they are fully open or starting to wilt. Harvest them the day they will be used.
• Snip the seed pods from the stems using scissors while they are still green. They can be used as a substitute for capers. Pickle them in vinegar.
• Leaves or stems can be stored for a few days in the fridge.
• When serving edible flowers fresh, add them to your dish just before serving.
• Collect Nasturtium seeds when they are ripe, dry them, and store them in a paper envelope in a cool and dark place. In mild areas, the plant is also likely to self-sow and volunteer year after year.

Propagating

• Nasturtium is propagated easily from seed or cuttings.

Pest and Diseases

• Nasturtium has no serious pest or disease issues. However, some problems may occasionally occur:
• Aphids: Leaves, stems, and buds distorted.
• Leaf miners: Leaves with tan or brown blotches or serpentine tunnels.
• Bacterial wilt: Plant yellows, wilts, and dies.
• Flea beetles: Leaves with many tiny holes.