Nasturtium illustration 🌺

🌺 Growing Nasturtium in Zone 3a

Zone 3a has harsh winters and a short growing season. Start Nasturtium early indoors to maximize your harvest window. Last frost: May 22. First frost: Sep 12.

Planting Calendar

Indoor
Outdoor
Harvest
Apr 24Sep 12

Season: May 22 – Sep 12 (113 days)

Zone3a
Last FrostMay 22
First FrostSep 12
Season Length113 days
Days to Harvest45
SunFull Sun
Frost ToleranceNone
Spacing4/sqft (6" apart)

When to Plant Nasturtium in Zone 3a

Start Seeds Indoors: Apr 24

Start Nasturtium seeds indoors around Apr 24 (4 weeks before last frost). Optimal germination temperature: 70°F. Germinates in 7–14 days.

Transplant Outdoors: May 29

Transplant Nasturtium seedlings outdoors after May 29. Wait until soil temperature reaches 55°F. Space plants at 4/sqft (6" apart). Harden off plants for a week before moving outside.

Harvest: Jul 8

First harvest approximately Jul 8 (~40 days from transplant). Continue harvesting until first frost (Sep 12).

Companion Planting

✅ Cucumbers✅ Squash✅ Pumpkins✅ Radishes✅ Cabbage

Frequently Asked Questions

When should I plant Nasturtium in Zone 3a?

Start Nasturtium seeds indoors around Apr 24. Transplant outdoors after May 29. Expect first harvest around Jul 8.

What is the last frost date for Zone 3a?

The average last spring frost date for Zone 3a is May 22. The first fall frost averages Sep 12, giving a 113-day growing season.

Can I grow Nasturtium in Zone 3a?

Yes. Nasturtium needs 45 days to harvest. Zone 3a has a 113-day growing season, which is sufficient.

What is the best month to plant Nasturtium in Zone 3a?

The best time to start Nasturtium in Zone 3a is Apr. Begin seeds indoors around Apr 24, then transplant outdoors after the last frost date of May 22.

What companion plants grow well with Nasturtium?

Good companion plants for Nasturtium include Cucumbers, Squash, Pumpkins, Radishes, Cabbage.

How long does Nasturtium take to harvest?

Nasturtium takes approximately 45 days from planting to harvest. In Zone 3a, expect your first harvest around Jul 8.

Plan Your Nasturtium Garden

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

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