Harman US

Planting Calendar for ZIP 06231

Based on your local frost dates - last spring frost around Apr 28, first fall frost around Oct 13 - here is when to plant 79 common crops near ZIP 06231.

Last spring frost
Apr 28
First fall frost
Oct 13
Hardiness zone
6b

Vegetables

Crop Start seeds indoors Plant outside Fall planting by
Tomatoes Mar 17 May 5 (Transplant out) -
Peppers Mar 3 May 12 (Transplant out) -
Cucumbers Apr 7 May 5 (Transplant out) Aug 5
Zucchini Apr 7 May 5 (Transplant out) Aug 10
Summer Squash Apr 7 May 5 (Transplant out) Aug 8
Winter Squash Apr 7 May 5 (Transplant out) -
Pumpkins Apr 7 May 5 (Transplant out) -
Green Beans - Apr 28 (Direct sow) Aug 5
Sweet Corn - May 5 (Direct sow) -
Melons Apr 7 May 12 (Transplant out) -
Watermelon Apr 7 May 12 (Transplant out) -
Okra - May 12 (Direct sow) -
Eggplant Mar 3 May 12 (Transplant out) -
Lettuce Mar 31 Mar 31 (Transplant out) Aug 10
Spinach - Mar 17 (Direct sow) Aug 15
Kale Mar 17 Apr 7 (Transplant out) Aug 5
Peas - Mar 17 (Direct sow) Jul 31
Carrots - Apr 7 (Direct sow) Jul 21
Beets - Mar 31 (Direct sow) Aug 5
Radishes - Mar 31 (Direct sow) Sep 1
Broccoli Mar 17 Apr 14 (Transplant out) Jul 26
Cauliflower Mar 17 Apr 14 (Transplant out) Jul 21
Cabbage Mar 17 Apr 7 (Transplant out) Jul 21
Onions Feb 17 Mar 31 (Transplant out) -
Potatoes - Apr 14 (Direct sow) -
Swiss Chard Mar 31 Apr 14 (Transplant out) Aug 5
Sweet Potatoes - May 19 (Direct sow) -
Brussels Sprouts Mar 17 Apr 14 (Transplant out) Jun 21
Celery Feb 17 May 5 (Transplant out) -
Leeks Feb 17 Apr 14 (Transplant out) Jun 1
Turnips - Apr 14 (Direct sow) Aug 10
Rutabaga - Apr 28 (Direct sow) Jun 26
Parsnips - Apr 14 (Direct sow) Jun 1
Kohlrabi Mar 31 Apr 14 (Transplant out) Aug 5
Collard Greens Mar 17 Apr 14 (Transplant out) Jul 26
Mustard Greens - Apr 14 (Direct sow) Aug 15
Arugula - Apr 14 (Direct sow) Aug 20
Bok Choy Mar 31 Apr 14 (Transplant out) Aug 10
Green Onions - Apr 14 (Direct sow) Jul 31
Tomatillos Mar 17 May 5 (Transplant out) -
Fennel Mar 31 Apr 14 (Transplant out) Jul 11
Popcorn Apr 28 May 12 (Transplant out) -
Black-Eyed Peas Apr 28 May 12 (Transplant out) Jul 11
Lima Beans Apr 28 May 12 (Transplant out) -
Edamame Apr 28 May 12 (Transplant out) -
Peanuts Apr 28 May 12 (Transplant out) -
Globe Artichoke Mar 3 Apr 14 (Transplant out) Jul 1
Horseradish Apr 28 Apr 14 (Transplant out) -
Ground Cherries Mar 17 May 12 (Transplant out) -
Radicchio Mar 24 Apr 14 (Transplant out) Jul 21
Endive Mar 24 Apr 14 (Transplant out) Jul 1
Watercress Apr 7 Apr 14 (Transplant out) Jul 31
Sorrel Mar 17 Apr 7 (Transplant out) Jul 31
Sunchokes Apr 28 Apr 14 (Transplant out) -
Malabar Spinach Mar 17 May 12 (Transplant out) -
Amaranth Greens Apr 7 May 12 (Transplant out) Aug 15
Luffa Gourd Mar 17 May 12 (Transplant out) -
New Zealand Spinach Mar 31 May 12 (Transplant out) -
Fava Beans Apr 28 Mar 31 (Transplant out) Jul 6
Chayote Mar 31 May 12 (Transplant out) -
Corn Salad Apr 28 Mar 31 (Transplant out) Jul 31
Bitter Melon Mar 31 May 12 (Transplant out) -
Cardoon Mar 17 Apr 28 (Transplant out) -

Herbs

Crop Start seeds indoors Plant outside Fall planting by
Basil Mar 17 May 5 (Transplant out) -
Cilantro - Apr 14 (Direct sow) Aug 10
Parsley Mar 3 May 12 (Transplant out) Jul 16
Dill - May 5 (Direct sow) Jul 31
Lemon Balm Mar 17 Apr 28 (Transplant out) -
Borage Apr 28 Apr 28 (Transplant out) Aug 5
Chervil Apr 28 Apr 7 (Transplant out) Aug 5
Lemongrass Mar 3 May 12 (Transplant out) -
Summer Savory Mar 17 Apr 28 (Transplant out) -
Marjoram Mar 17 May 5 (Transplant out) -
Lovage Mar 17 Apr 28 (Transplant out) Jul 1
Anise Hyssop Mar 3 Apr 28 (Transplant out) -
Shiso Mar 17 May 5 (Transplant out) -
Stevia Mar 3 May 12 (Transplant out) -
Chamomile Mar 17 Apr 14 (Transplant out) Jul 26
Tarragon Apr 28 Apr 28 (Transplant out) -
How to read this calendar

Start seeds indoors is when to sow in trays inside so seedlings are ready to transplant. Plant outside is when to transplant seedlings or direct-sow seed, based on frost tolerance. Fall planting by is the latest date to start a fall crop and still harvest before the first fall frost. Tender crops wait until after the last spring frost; hardy crops can go out earlier.

Computed from NOAA 1991–2020 Climate Normals at Willimantic Windham Ap, Ct, 12.1 miles away. Averages for planning, not a forecast. Page updated Aug 4, 2026.

Full frost dates for 06231 Local weather →