When should I plant Nasturtium in Zone 4a?

Start Nasturtium seeds indoors around Apr 7. Transplant outdoors after May 12. Expect first harvest around Jun 21.

What is the last frost date for Zone 4a?

The average last spring frost date for Zone 4a is May 5. The first fall frost averages Oct 1, giving a 149-day growing season.

Can I grow Nasturtium in Zone 4a?

Yes. Nasturtium needs 45 days to harvest. Zone 4a has a 149-day growing season, which is sufficient.

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🌺 Growing Nasturtium in Zone 4a

Zone 4a has cold winters and a moderate growing season. Timing is key for Nasturtium in this zone. Last frost: May 5. First frost: Oct 1.

Planting Calendar

Indoor

Outdoor

Harvest

Apr 7Oct 1

Season: May 5 – Oct 1 (149 days)

Zone4a

Last FrostMay 5

First FrostOct 1

Season Length149 days

Days to Harvest45

SunFull Sun

Frost ToleranceNone

Spacing4/sqft (6" apart)

When to Plant Nasturtium in Zone 4a

Start Seeds Indoors: Apr 7

Start Nasturtium seeds indoors around Apr 7 (4 weeks before last frost). Optimal germination temperature: 70°F. Germinates in 7–14 days.

Transplant Outdoors: May 12

Transplant Nasturtium seedlings outdoors after May 12. Wait until soil temperature reaches 55°F. Space plants at 4/sqft (6" apart). Harden off plants for a week before moving outside.

Harvest: Jun 21

First harvest approximately Jun 21 (~40 days from transplant). Continue harvesting until first frost (Oct 1).

Companion Planting

✅ Cucumbers✅ Squash✅ Pumpkins✅ Radishes✅ Cabbage

Nasturtium in Other Zones

1a 1b 2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a 11b 12a 12b 13a 13b

Plan Your Nasturtium Garden

Track Nasturtium from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.

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