How to Grow Nasturtium
Nasturtium At a Glance
Difficulty
Easy
Category
Flower
Sun Exposure
Full Sun, Partial Sun
Frost Tolerance
Frost Tender
Cold Hardiness
Survives to 2°C
Plant Family
Tropaeolaceae
Growing Season
Warm Season
Plant Lifecycle
Annual
How to Start It
★ Recommended for beginners
Nasturtiums are killed by frost, so sow them about 1 week after your last spring frost, right where they will grow. Soak the big seeds in water overnight, then push them 1 cm deep, 25 cm apart. They sprout in 7 to 14 days. Do not fuss over them: poor soil gives the most flowers.
Nasturtiums are almost foolproof, and the leaves, flowers and green seed pods are all edible, with a peppery taste like watercress. They work as a lure in the garden: aphids often go for them instead of your vegetables, and bees love the flowers. Trailing types spill nicely from pots and baskets, and dropped seeds often come back the next year.
When To Start
First chance to plant
7 Days After Last Frost
Last chance to plant
30 Days Before First Frost
When should you plant Nasturtium?
Your planting dates depend on your local climate. Sign up and add your location to unlock personalized dates.
Your Nasturtium Planting Window
Start planting
May 15, 2026
Last chance
Sep 10, 2026
Your Nasturtium Calendar
Set your location to turn these into exact dates and reminders.
Sow nasturtiums outdoors now, in plain soil for more flowers
1 week after your last frost· every year
Optional: start nasturtiums indoors in paper pots
3 weeks before your last frost· every year· optional
Pick nasturtium flowers and leaves to keep them coming
50 days after your last frost· every year· optional
Did you water your nasturtium seedlings today? Keep the top of the soil damp until they are up and growing.
About 1 days after you plant it
Your nasturtiums are growing! Go easy on watering and skip rich soil, too much makes more leaves than flowers.
About 34 days after you plant it
Bloom time! Pick flowers and young leaves often to keep new ones coming.
About 54 days after you plant it
Picking time may be here: check your nasturtium.
About 60 days after you plant it
The Journey Ahead
Nasturtium's Lifecycle
Seedling
Mature Plant
Seed Production
Step 2
Planting & Sprouting
Expect sprouts in 7–14 days
Growing Tips
- 1Plant nasturtiums in full sun, at least 6 hours a day, for the most flowers.
- 2Skip the compost and rich soil here, because rich soil gives big leaves and very few flowers.
- 3Water when the top few cm of soil is dry, a bit more often in pots.
- 4Do not feed them at all, unless they are in a pot and look pale.
- 5Black aphids love nasturtiums, so blast them off with a spray of water, or pull and toss a stem that is covered in them.
- 6Grow a few near squash, cabbage and beans, where they pull aphids away from your crops.
Seedling Phase
Step 3
Growth & Maturity
~60
Days to Maturity
30 cm
Mature Height
45 cm
Mature Width
Pests to Watch For
Diseases to Watch For
Mature Plant
Step 4
Harvesting
Harvest Window
45 days
When to Pick
Pick flowers and young leaves regularly
How to Harvest
- 1Pick flowers and young leaves in the morning, when they are crisp.
- 2Pinch or snip each stem just above a leaf, so the plant keeps making more.
- 3Pick faded flowers every few days to keep new ones coming all summer.
- 4Use the flowers and leaves fresh in salads, since they wilt quickly once picked.
- 5Pick the green seed pods while they are still soft and pickle them in vinegar, like capers.
- 6Keep picked flowers in a bag in the fridge and use them within a day or two.
Step 5
Saving Seeds
How to Save Seeds
Nasturtium seeds come true if the variety is not a hybrid (hybrid F1 seeds will not), but bees can cross different nasturtium varieties, so expect mixed colours if you grow several. Let a few flowers fade on the plant until the wrinkled seeds turn tan and drop off by themselves, then gather them from the plant and the ground. Spread them out indoors for 2 to 3 weeks until they are fully dry and hard, because these big seeds rot if stored damp. Store them labelled in a paper envelope in a cool, dark, dry place, where they keep at least 3 years.
Seed Production
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