How to Grow Nasturtium

Botanical Name: Tropaeolum Majus

A native to South America. It is well-known for its vivid blooms and tasty, peppery leaves.

Easy to cultivate, nasturtiums are frequently used as companion plants and in salads.

Do you want to learn how to grow Nasturtium seeds? If so, let’s dive in.

  • How to Grow Nasturtium
  • How to Grow Nasturtium
Planting Guide Image

Nasturtium Planting Guide

Method

Sow direct or raise seedlings

Sowing Depth

15 mm

Season

Spring

Germination

7-14 days @ 16-20°C

Hardiness / Life Cycle

Frost tender Annual

Row Spacing

30 cm

Plant Spacing

30-45 cm

Position

Part or full sun, moist well-drained soil

Days Until Maturity

70-80 days

Storage

Refrigerate in a plastic bag with a damp paper towel

When to Plant Nasturtium in Australia

What growing
region am I in?
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Cool Plantable in Sep Plantable in Oct Plantable in Nov Plantable in Dec
Mild Plantable in Jan Plantable in Feb Plantable in Aug Plantable in Sep Plantable in Oct Plantable in Nov Plantable in Dec
Sub-Tropical Plantable in Feb Plantable in Mar Plantable in Apr Plantable in May Plantable in Jun Plantable in Jul Plantable in Aug Plantable in Sep
Tropical Plantable in Feb Plantable in Mar Plantable in Apr Plantable in May Plantable in Jun Plantable in Jul Plantable in Aug Plantable in Sep
Arid Plantable in Feb Plantable in Mar Plantable in Apr Plantable in May Plantable in Jun Plantable in Jul Plantable in Aug Plantable in Sep
Cool Mild Sub-Tropical Tropical Arid
Jan Plantable in Jan
Feb Plantable in Feb Plantable in Feb Plantable in Feb Plantable in Feb
Mar Plantable in Mar Plantable in Mar Plantable in Mar
Apr Plantable in Apr Plantable in Apr Plantable in Apr
May Plantable in May Plantable in May Plantable in May
Jun Plantable in Jun Plantable in Jun Plantable in Jun
Jul Plantable in Jul Plantable in Jul Plantable in Jul
Aug Plantable in Aug Plantable in Aug Plantable in Aug Plantable in Aug
Sep Plantable in Sep Plantable in Sep Plantable in Sep Plantable in Sep Plantable in Sep
Oct Plantable in Oct Plantable in Oct
Nov Plantable in Nov Plantable in Nov
Dec Plantable in Dec Plantable in Dec
What growing
region am I in?

Growing Nasturtium

Nasturtiums are vibrant, easy-to-grow plants that add a splash of colour to any garden. In this guide, we’ll explore the different types of nasturtiums, their edibility, planting times in Australia, and tips on growing them successfully from seeds.

Nasturtium Types

Nasturtiums come in a variety of types, each with unique characteristics:

Tropaeolum majus: The most common type, with trailing or climbing varieties.

Tropaeolum minus: A dwarf variety suitable for borders and containers.

Tropaeolum peregrinum: Known as the Canary Creeper, with unique yellow flowers.

Are Nasturtiums Edible?

Yes, nasturtiums are entirely edible. Their leaves, flowers, and seeds have a peppery flavour, similar to watercress. They make a colourful and spicy addition to salads, garnishes, and even pestos.

When to Plant Nasturtium in Australia

The best time to plant nasturtiums in Australia depends on your climate zone:

  • Temperate zones: Plant in early spring after the last frost.
  • Subtropical and tropical zones: Plant during the cooler months, avoiding the hottest part of the year.
  • Cooler regions: Plant indoors 4-6 weeks before the last frost, then transplant outside.

Where to Plant Nasturtium in Vegetable Garden

Nasturtiums thrive in well-drained soil with full sun to partial shade. Plant them along borders, in containers, or as companion plants in your vegetable garden. They are particularly effective at deterring pests and attracting beneficial insects.

How to Grow Nasturtiums from Seeds

Growing nasturtiums from seeds is an easy and rewarding process. These vibrant plants add a splash of colour to your garden and serve as excellent companions to other plants by repelling pests. Here’s a step-by-step guide to growing nasturtiums from seeds.

Soaking Nasturtium Seeds

Before planting, it’s beneficial to soak nasturtium seeds in warm water overnight. This helps soften the hard outer shell of the seeds, promoting faster and more successful germination.

Planting Nasturtium Seeds

1. Choose the Right Location:

  • Nasturtiums prefer full sun but can tolerate partial shade.
  • Ensure the soil is well-drained. Nasturtiums thrive in poorer soils; too much fertiliser can lead to lush foliage at the expense of flowers.

2. Prepare the Soil:

  • Loosen the soil to a depth of about 15-20 cm.
  • If your soil is very rich, you may want to amend it with sand or a bit of compost to improve drainage.

3. Plant the Seeds:

  • Sow seeds directly into the ground after the last frost in temperate zones or during the cooler months in subtropical and tropical regions.
  • Plant seeds about 1.5 cm deep and 25-30 cm apart. If you’re planting in rows, space the rows about 30-40 cm apart.

4. Watering:

  • Water the seeds thoroughly after planting.
  • Keep the soil consistently moist until the seeds germinate, which typically takes 7-10 days.
  • Once established, nasturtiums are quite drought-tolerant. Water them moderately, allowing the soil to dry out slightly between waterings.

5. Thinning:

  • If seedlings are too crowded, thin them to ensure they have enough space to grow. This helps prevent disease and promotes healthy growth.

Caring for Nasturtiums

1. Mulching:

  • Mulch around the plants to retain moisture and suppress weeds. Be careful not to cover the stems, as this can cause rot.

2. Feeding:

  • Nasturtiums typically do not require fertilisation. Over-fertilising can reduce flower production and lead to excessive foliage growth.

3. Pruning:

  • Regularly remove dead or yellowing leaves to maintain plant health and appearance.
  • Pinch off spent flowers to encourage continuous blooming.

4. Pest Control:

  • Nasturtiums are generally pest-resistant, but they can attract aphids and black fly. Use a mild soapy water spray to control these pests if necessary.

Companion Planting with Nasturtiums

Nasturtiums make excellent companion plants for many vegetables, including tomatoes, cucumbers, and cabbages. They can help deter pests and attract beneficial insects, enhancing the overall health and productivity of your garden.

By following these steps, you can enjoy the beauty and benefits of nasturtiums in your garden. Their vibrant flowers and easy-going nature make them a favourite among gardeners of all levels.

What Not to Plant with Nasturtiums

When planning your garden, it’s important to consider plant compatibility. While nasturtiums are excellent companions for many vegetables and flowers, there are some plants that should not be grown alongside them. Understanding these incompatibilities can help you create a more harmonious and productive garden.

Nasturtium and Beans

Nasturtiums and beans, particularly pole beans, should not be planted together. Both plants are vigorous growers and can compete for the same resources, such as nutrients, sunlight, and space. This competition can hinder the growth and productivity of both plants. Additionally, the dense foliage of nasturtiums can create a humid environment that favours fungal diseases, which can affect beans.

Nasturtium Problems

While nasturtiums are generally easy to grow and resilient, they can encounter a few problems. Understanding these issues and knowing how to address them will help ensure your nasturtiums remain healthy and vibrant.

Nasturtium Black Fly

One of the most common problems nasturtiums face is an infestation of black fly (aphids). These small, sap-sucking insects can cause significant damage to your plants if not controlled.

Identifying Black Fly

Appearance: Black flies are small, dark-coloured insects that cluster on the stems, leaves, and flower buds of the plant.

Symptoms: Infested plants may have curled or yellowing leaves, stunted growth, and a sticky residue (honeydew) on the foliage.

Controlling Black Fly

Natural Predators: Introduce natural predators like ladybirds and lacewings, which feed on aphids.

Soapy Water Spray: Mix a few drops of mild dish soap with water and spray the affected plants. The soapy solution suffocates the aphids without harming the plants.

Neem Oil: Neem oil is an organic insecticide that can be sprayed on the plants to control aphid populations.

Companion Planting: Plant nasturtiums alongside aphid-repelling plants like garlic and chives.

Other Common Nasturtium Problems

1. Powdery Mildew:

  • Symptoms: White, powdery fungal growth on leaves and stems.
  • Prevention and Treatment: Ensure good air circulation, avoid overhead watering, and remove affected plant parts. Fungicides may also help.

2. Leaf Spot:

  • Symptoms: Brown or black spots on leaves, which may eventually lead to leaf drop.
  • Prevention and Treatment: Remove and dispose of infected leaves, avoid overhead watering, and maintain proper plant spacing for good air circulation.

3. Slugs and Snails:

  • Symptoms: Irregular holes in leaves, often with a shiny slime trail.
  • Prevention and Treatment: Use slug traps, barriers, or organic slug pellets. Hand-picking slugs and snails can also be effective.

4. Root Rot:

  • Symptoms: Wilting, yellowing leaves, and stunted growth, often caused by waterlogged soil.
  • Prevention and Treatment: Ensure well-draining soil and avoid overwatering. If root rot occurs, improve drainage and remove affected plants to prevent the spread.

General Tips for Healthy Nasturtiums

  • Watering: Water at the base of the plants to keep foliage dry and reduce the risk of fungal diseases.
  • Soil: Plant nasturtiums in well-drained soil and avoid overly rich soil, which can lead to excessive foliage growth at the expense of flowers.
  • Spacing: Provide adequate spacing between plants to ensure good air circulation and reduce the risk of disease.

By monitoring your nasturtiums regularly and addressing problems promptly, you can enjoy healthy, thriving plants throughout the growing season.

Growing Nasturtiums in Pots

Nasturtiums are well-suited for container gardening. Choose a pot with good drainage, fill it with well-draining soil, and place it in a sunny spot. Water regularly but avoid overwatering, as nasturtiums prefer slightly dry conditions.

How to Train Nasturtiums to Climb

To train nasturtiums to climb, provide a trellis or support structure. Gently tie the stems to the support with garden twine, guiding them as they grow. Regularly check and adjust the ties to ensure the stems are not damaged.

When Do Nasturtiums Flower

Nasturtiums typically flower from late spring to early autumn. The exact timing can vary depending on the planting time and climate. Regular deadheading can encourage continuous blooming.

Do Nasturtiums Come Back Every Year

Do Nasturtiums Self Seed

Nasturtiums are annuals, but they often self-seed. If you leave the spent flowers on the plant, they will produce seeds that drop to the ground and germinate the following spring, ensuring a new generation of plants each year.

Growing nasturtiums from seeds is a rewarding experience that adds beauty and functionality to your garden. With the right care and attention, you can enjoy these delightful plants year after year.

Conclusion

Growing nasturtiums from seeds is a straightforward and rewarding endeavour that adds vibrant colour and edible beauty to any garden. By understanding the different types of nasturtiums, their planting requirements in Australia, and how to care for them, you can enjoy a bountiful display of flowers throughout the growing season.

Whether you're growing them in pots, training them to climb, or using them as companion plants in your vegetable garden, nasturtiums are versatile and beneficial. With their ability to self-seed, you can look forward to their cheerful blooms year after year, making them a delightful addition to your gardening repertoire.