Watercress in Zone 3a & 3b
Nasturtium officinale
Yes, watercress grows in zones 3a and 3b. Start seeds indoors May 9–May 16 and plant out May 16–May 23.
When to plant watercress in zone 3b
Zones 3a and 3b share the same average frost dates, so this page covers both.
Method: Either: Start indoors for an earlier harvest, or direct-sow outside for less fuss. Either works.
| Start indoors | May 9–May 16 |
|---|---|
| Direct sow / transplant outside | May 16–May 23 |
| Estimated harvest | Jul 5–Jul 12 (~50 days after planting) |
Spacing: 9 per square foot (square-foot-gardening spacing). Mature height: 4-10 in.
Plant alongside it in zone 3b
These go outside within two weeks of watercress in zone 3b, so one planting day can cover them.
- OnionMay 9–May 16
- RadishMay 2–May 9
- CarrotMay 9–May 16
- CabbageMay 16–May 23
- LettuceMay 16–May 23
- BroccoliMay 16–May 23
Watercress is the plant upland cress is compared against and named for, a peppery salad green that shares its flavor but is harder to grow, since it needs constantly saturated soil rather than an ordinary garden bed.
How watercress fits zone 3's season
Zone 3b's frost-free window runs about 98 days, from May 30 to September 5. Watercress needs about 50 days from sowing to first harvest.
Watercress planting windows in every zone
Zone 3b is highlighted. Useful for comparing against a neighbouring zone, or for a garden somewhere else.
| Zone | Start indoors | Sow or plant out | Harvest |
|---|---|---|---|
| 3a & 3b (your zone) | May 9–May 16 | May 16–May 23 | Jul 5–Jul 12 |
| 4a & 4b | Apr 24–May 1 | May 1–May 8 | Jun 20–Jun 27 |
| 5a & 5b | Apr 19–Apr 26 | Apr 26–May 3 | Jun 15–Jun 22 |
| 6a & 6b | Apr 4–Apr 11 | Apr 11–Apr 18 | May 31–Jun 7 |
| 7a & 7b | Mar 20–Mar 27 | Mar 27–Apr 3 | May 16–May 23 |
| 8a & 8b | Mar 4–Mar 11 | Mar 11–Mar 18 | Apr 30–May 7 |
| 9a & 9b | Jan 25–Feb 1 | Feb 1–Feb 8 | Mar 23–Mar 30 |
| 10a & 10b | Jan 9–Jan 16 | Jan 16–Jan 23 | Mar 7–Mar 14 |
Harvest dates are about 50 days after the sow or plant-out date, not after starting seeds indoors.
Good companions
No well-established companions for watercress.
Where to buy watercress seeds
Botanical Interests (each supplier's watercress seeds)
See why we recommend these suppliers →
As an Amazon Associate we earn from qualifying purchases. Some links on this page also go to other retailers we may earn a commission from as an affiliate, at no extra cost to you. We only recommend products with a clear consensus of positive, independent reviews, or ones we bought and use ourselves. Each item on our gear page says which.
See it growing
Search YouTube for "growing watercress" videos → (a live search, not a hand-picked video; results vary and aren't vetted by us)
← Back to the full zone 3b calendar · Plan your beds in the Garden Designer →
Pin this for later
Growing Watercress in USDA zone 3b: when to start seeds indoors, when to direct-sow, and when to expect a harvest.
Save to Pinterest