Climbing nasturtium: How to grow this colorful annual vine

Climbing nasturtium plants are the perfect annual flower to grow vertically on fences, trellises, and arches. The vigorous stems grow 5 to 6 feet in length and the vines flower non-stop from mid-summer until frost. Bees and hummingbirds love the cup-shaped flowers which come in brilliant shades of red, orange, gold, pink, and cream, as well as many bi-colors. The best part? Climbing nasturtiums are super easy to grow in garden beds and containers. Keep reading to learn more about how to plant, grow, and care for climbing nasturtiums plants. 

What is a climbing nasturtium?

Nasturtiums (Tropaeolum majus) are among the most popular of the annual flowers and beloved for their ease of cultivation and quick growth. The vigorous plants produce masses of large rounded leaves and brightly colored flowers, both of which are edible and delicious in salads. The fragrant, cup-shaped blooms come in shades of reds, oranges, yellows, and creams, as well as pink, apricot, peach, and purple. Many varieties offer bi-colored blooms with splotches or streaks that add another layer of interest to the summer garden. 

Nasturtiums are typically divided into two categories: mounding and climbing. Mounding nasturtiums form bushy plants that grow about 15 inches tall and wide. Their tidy growth habit makes them ideal as edging plants in raised beds or along pathways, and are also perfect for pots, window boxes, and planters. Climbing, or trailing nasturtiums, on the other hand, have vigorous branches and are often grown up trellises and supports. Or, you can let them wander along the ground as a ground cover. They make an excellent living mulch between crops like corn and tomatoes, shading the soil to suppress weeds and retain moisture.

I plant both mounding and climbing nasturtiums in my large vegetable garden as they add vibrant color to my beds and attract beneficial and pollinating insects like bees, hover flies, and ladybugs, as well as hummingbirds.

Where to grow climbing nasturtiums

All nasturtiums thrive when planted in full sun. You can grow them in part shade, but the stems stretch and become leggy and the plants produce fewer flowers. As for soil, climbing nasturtiums grow well in poor to average soil that is well-draining. There’s no need to go to the extra trouble of amending and fertilizing garden beds. A very fertile soil results in lush, leafy growth but few nasturtium flowers. The exception is container grown nasturtiums which benefit from an occasion feed. 

How to plant climbing nasturtium seeds

Nasturtiums can be direct sown in a garden bed or container when the danger of frost has passed in mid-spring. The tender plants aren’t tolerant of frosts so don’t sow the seeds too early. Plant climbing nasturtium seeds a 1/2 inch deep and space them 10 to 12 inches apart at the base of a trellis, fence, or other structure. When growing them up the posts of an obelisk or teepee, plant three seeds at the base of each post, eventually thinning to two seedlings. Once the seeds are sown, water the bed well to encourage germination. Nasturtiums seeds typically sprout in 7 to 10 days. 

You can give climbing nasturtiums a head start by sowing the seeds indoors under grow lights or in a sunny window. They need a strong light source to grow well. Sow seeds indoors 4 weeks before you intend to transplant them into the garden. I use 4 inch diameter pots and plant two seeds per pot. Poke seeds a 1/2 inch deep and press soil lightly to ensure good soil-seed contact. Once the seeds sprout, thin to one plant per pot. About a week before transplanting, harden off the seedlings by slowly acclimating them to sunlight and outdoor growing conditions.

How to transplant climbing nasturtiums

If you bought climbing nasturtium seedlings or started your own indoors, plant them outside in garden beds or containers after the last frost has passed. Carefully slip the seedling from the pot or cell pack and place it in the planting hole. Transplant seedlings at the same depth they were growing in the pot. Take care to not disturb the roots which can set the plants back. Refill the planting hole and gently tamp down the soil. Water the bed or container after planting. I like to use a watering wand with a shower setting to ensure a soft spray of water. 

The best supports for climbing nasturtium plants

As noted above, you can let climbing nasturtium plants wander through your garden or grow them up supports. I prefer to grow them vertically to best show off their eye-catching foliage and flowers, often interplanting them with vining vegetables like pole beans and cucumbers. Below are 4 types of supports perfect for climbing nasturtiums. 

1. Trellises – At the back of my raised bed vegetable garden I mounted 6 foot tall wooden stakes with 4 by 8 foot wire mesh panels to create simple DIY trellises. These flat trellises provide sturdy support for climbing nasturtium plants. Other options for flat trellises are sheets of wooden lattice or wall-mounted trellises. 
2. Obelisks – Obelisks are pyramidal shaped structures that add style and support to a garden. They may be made from wood or metal and can be DIY’d or bought from garden supply stores. 
3. Tunnels or Arches – I love my pole bean tunnels which I made from two 4 by 8 sheets of wire mesh panel mounted to my wooden raised beds. You can also make tunnels from 16 foot long cattle panels or buy metal, wood, or plastic arches. Tunnels are extremely ornamental garden features, but also perfect for vining vegetables and flowers like climbing nasturtiums. 
4. A-frame Trellis – Another option is to DIY or buy an A-frame trellis. These are typically made from wood, wire panels, or metal tubing and have two sections that are joined at the top to create an A-shape. I use them for heavy crops like cucumbers and vining squash, tucking a few climbing nasturtiums seeds at the posts to add color and attract pollinators. 

Do you need to train climbing nasturtiums?

Annual vines can climb in a variety of ways. Some, like sweet peas produce tendrils that cling to supports. Others, like morning glory have stems that twine around trellises. Climbing nasturtium plants produce vigorous branches that are directed up trellises, fences, arbors, and other supports. Do this when the plants are young. I weave the stems vertically through wire trellises or secure them to wooden structures with loose plant ties. Be careful as the stems of nasturtiums can break easily. When the early growth is directed up, the plants easily and enthusiastically climb.

Can you grow climbing nasturtium plants in containers? 

Climbing nasturtiums are also ideal for pots, window boxes, and hanging baskets. The key is to select a container that can accommodate the vigorous plants. A 15 to 18 inch diameter pot or hanging basket offers enough room for several climbing nasturtium plants. Also look for a pot with drainage holes as nasturtiums don’t grow well in wet soil. When it’s time to plant, direct sow 4 seeds per pot, eventually thinning to 2 to 3 plants by removing the weaker seedling. You can also transplant a couple of climbing nasturtium seedlings into each pot. 

If you’re growing climbing nasturtiums in a hanging basket, the stems will tumble down over the sides of the pot. If you are growing them in a container or planter you should provide support with a pot trellis or place the container at the base of a trellis or fence. 

Caring for nasturtium plants

Climbing nasturtiums are carefree garden annuals and thrive with little fussing. That said there are a few tasks you can do to promote lush, healthy growth:

1. Train the plants – Initially, I train the young plants vertically by tying them to their supports with soft garden ties or plant clips. This is not necessary if you’re growing them on the ground. 
2. Water – Garden-grown nasturtiums are reasonably drought tolerant, but benefit from an occasional watering if there has been no rain for a week or two. Stick your finger into the soil and if it’s dry 2 inches down, water. I like to use a long-handled watering wand. Water container-grown nasturtiums every day or two, depending on the weather. Again, test soil moisture with your finger and water if it’s dry 2 inches down. 
3. Fertilize – I don’t fertilize climbing nasturtium plants that are growing in my garden beds, but I do apply an organic flowering plant fertilizer to container plants every 2 to 3 weeks in summer. 
4. Deadhead – You don’t need to deadhead the flowers of climbing nasturtiums, but removing spent blooms or seed clusters promotes the production of new flowers. 
5. Watch for pests – Aphids are the most common pest of climbing nasturtiums. The tiny, sap-sucking insects often cluster on leaf or flower stems. I don’t mind aphids on my nasturtiums as they provide food for predatory insects like ladybugs and lacewings. If you wish to remove aphids use a jet of water from a hose or spray an insecticidal soap. 

The best climbing nasturtiums to grow

In many climates nasturtiums self-sow from year to year. In colder regions you’ll need to replant each spring. Below are some outstanding climbing nasturtium varieties you may wish to try. 

Climbing nasturtium varieties:

• Cherrelle – This striking climbing variety produces hundreds of double flowers in an electric shade of raspberry-red. The trailing stems grow up to 5 feet long and are perfect for wandering up fences, trellises, and obelisks. 
• Yeti – Yet is an unusual climbing nasturtium for its pale cream colored blooms and large waterlily leaves. Each vine is loaded with the delicate-looking flowers that are beautiful in the garden, the salad bowl, or bouquets. 
• Spitfire – Grow Spitfire for its intense scarlet-red blooms which are excellent for attracting hummingbirds to the garden. Plant the seeds or seedlings at the base of supports or let them spill over the sides of hanging baskets and containers.
• Gleam Salmon – As the name suggests, the blooms of Gleam Salmon are a gorgeous salmon-peach hue. This novel color contrasts nicely with the deep green leaves. Direct the 5 to 6 foot long vines up structures or encourage them to roam through the garden.

Climbing nasturtium seed mixes:

Buying a climbing nasturtium seed mix is an easy way to enjoy a blend of colors without needing to buy a bunch of separate seed packets.

• Kaleidoscope mix – Kaleidoscope mix is a fiery collection of red, orange, cream, rose, and yellow bloomers with many of the flowers having bi-colored swirls and streaks. 
• Trailing mix – This is a classic mixture of red, orange, yellow, and pink climbing nasturtium varieties. Enjoy a profusion of brilliant blooms from mid-summer until frost. 
• Amazon Jewel – Expect oohs and ahhs from garden visitors when they spot this unique variety. The flowers are painted in glowing shades of orange, pink, gold, lemon, and ruby, as well as several bi-colors. The variegated leaves add another layer of interest with each rounded leaf streaked in cream. 
• Climbing Phoenix – This is one of my favorite climbing nasturtium varieties for its unusual split-petal flowers. What does that mean? Instead of being fused into a cup-shape, the petals of Phoenix nasturtiums are separate and have spiky edges which makes each one look like a small flame. The color range includes gold, orange, burgundy, and apricot, with the blossoms often having attractive splotches. The plants have stems that climb or ramble 3 to 4 feet. 

For more information on growing annual flowers, we recommend these articles:

• When to plant zinnias for months of beautiful blooms
• When to plant sunflowers: 3 easy options
• Zinnia profusion – Grow an abundance of carefree zinnias
• How to grow Salpiglossis, the painted tongue flower
• Growing marigolds from seed

Are you going to sow any climbing nasturtium seeds in your garden this spring?