Trenton, New Jersey planting calendar and frost dates
Trenton is in USDA hardiness zone 7b. The last spring frost typically comes around April 10 and the first fall frost around November 1, giving about 202 frost-free days a year.
- Typical last frost
- April 10
- Typical first frost
- November 1
- Frost-free season
- 202 days
Frost dates in Trenton
Last spring frost
- March 30Risky: frost later than this in 9 years out of 10
- April 10Typical: a later frost in half of years
- April 25Safe: a later frost only 1 year in 10
First fall frost
- October 15Risky: frost earlier than this 1 year in 10
- November 1Typical: an earlier frost in half of years
- November 13Late: frost before this in 9 years out of 10
The growing season between the typical last and first frosts is about 202 days. Frost here means a low of 32°F at the weather station. A hard freeze (28°F), which damages most hardy crops too, typically ends around March 31 and returns around November 12.
NOAA U.S. Climate Normals 1991-2020 for Trenton Mercer Co Airport, 2.3 miles NW of the city center. Low-lying and rural spots often frost later in spring and earlier in fall than airports and city centers.
What to plant each month in Trenton
January
Start indoors: broccoli, cabbages, cauliflower, collard greens, kale, leeks, onions, oregano, parsley, petunias, ranunculus, rosemary, snapdragons
February
Start indoors: black-eyed susans, broccoli, cabbages, cauliflower, chives, cilantro, collard greens, ginger, kale, leeks, lettuce, marigolds, nasturtiums, oregano, parsley, peppers, petunias, ranunculus, rosemary, sage, snapdragons, spinach, swiss chard
Plant or sow outdoors: black-eyed susans, blueberries, garlic, grapes, grass seed, hollyhocks, onions, peas, poppies, raspberries, rhubarb, strawberries, turnips, wildflowers
March
Start indoors: basil, celery, cilantro, eggplants, ginger, marigolds, nasturtiums, peppers, ranunculus, spinach, swiss chard, tomatoes
Plant or sow outdoors: beets, black-eyed susans, blackberries, blueberries, broccoli, cabbages, carrots, cauliflower, chives, cilantro, collard greens, dahlias, dill, figs, garlic, gladioli, grapes, grass seed, hollyhocks, kale, leeks, lettuce, onions, parsley, peas, poppies, radishes, ranunculus, raspberries, rhubarb, roses, snapdragons, spinach, strawberries, swiss chard, turnips, wildflowers
April
Start indoors: basil, cantaloupes, cosmos, cucumbers, okra, pumpkins, watermelons, winter squash, zucchini
Plant or sow outdoors: asparagus, beets, carrots, cauliflower, chives, cilantro, dahlias, dill, figs, garden mums, ginger, gladioli, grapes, green onions, kentucky bluegrass, lavenders, leeks, lettuce, lilies, marigolds, mints, nasturtiums, oregano, parsley, perennial ryegrass, petunias, potatoes, ranunculus, rosemary, roses, sage, snapdragons, spinach, sunflowers, sweet corn, sweet peas, swiss chard, tall fescue, thyme
May
Start indoors: zinnias
Plant or sow outdoors: asparagus, basil, bermudagrass, cantaloupes, celery, centipedegrass, cosmos, cucumbers, eggplants, garden mums, ginger, green beans, green onions, kentucky bluegrass, okra, peanuts, peppers, perennial ryegrass, pumpkins, st. augustinegrass, sunflowers, sweet peas, sweet potatoes, tall fescue, tomatoes, watermelons, winter squash, zoysiagrass, zucchini
June
Plant or sow outdoors: bermudagrass, celery, centipedegrass, cosmos, green onions, okra, peanuts, st. augustinegrass, sweet potatoes, zinnias, zoysiagrass
July
Plant or sow outdoors: bermudagrass, centipedegrass, zoysiagrass
Plant for fall: brussels sprouts
August
Plant for fall: bearded irises, beets, broccoli, brussels sprouts, cabbages, carrots, cauliflower, collard greens, daylilies, kale, lettuce, peas, radishes, snapdragons, spinach, swiss chard, turnips
September
Plant for fall: azaleas, bearded irises, beets, broccoli, cabbages, cauliflower, clematis, coneflowers, crocuses, daffodils, daylilies, grass seed, hostas, hydrangeas, kale, kentucky bluegrass, lettuce, lilies, ornamental alliums, peonies, perennial ryegrass, radishes, roses, saffron, snapdragons, spinach, tall fescue, tulips, turnips
October
Plant for fall: crocuses, daffodils, daylilies, grass seed, hostas, hyacinths, kale, kentucky bluegrass, lilies, ornamental alliums, peonies, perennial ryegrass, radishes, saffron, tall fescue, tulips
November
Plant for fall: crocuses, daffodils, garlic, hyacinths, lilies, ornamental alliums, peonies, tulips
December
Start indoors: onions
Frost dates and zones by ZIP code in Trenton
All 6 of Trenton's main ZIP codes take their frost dates from Trenton Mercer Co Airport, so the dates on this page apply across the city. The hardiness zone is 7a in 08609, 08610, 08611, 08629, 08638, and 7b in 08618.
| ZIP code | Zone | Weather station | Typical last frost | Typical first frost |
|---|---|---|---|---|
| 08609 | 7a | Trenton Mercer Co Airport, 5.3 mi NW | Apr 10 | Nov 1 |
| 08610 | 7a | Trenton Mercer Co Airport, 7.8 mi NW | Apr 10 | Nov 1 |
| 08611 | 7a | Trenton Mercer Co Airport, 7.6 mi NNW | Apr 10 | Nov 1 |
| 08618 | 7b | Trenton Mercer Co Airport, 2.3 mi NW | Apr 10 | Nov 1 |
| 08629 | 7a | Trenton Mercer Co Airport, 5.9 mi NW | Apr 10 | Nov 1 |
| 08638 | 7a | Trenton Mercer Co Airport, 3.2 mi WNW | Apr 10 | Nov 1 |
Planting dates for popular crops in Trenton
| Plant | Start indoors | Plant or sow outdoors | Fall planting |
|---|---|---|---|
| Tomatoes | Mar 14 to 28 | May 9 to 23 | — |
| Strawberries | — | Feb 27 to Mar 13 | — |
| Lettuce | Feb 13 to 27 | Apr 3 to 17 | Aug 2 to Sep 6 |
| Cilantro | Feb 27 to Mar 13 | Apr 10 to 17 | — |
| Basil | Mar 21 to Apr 4 | May 9 to 16 | — |
| Potatoes | — | Apr 9 to 16 | — |
| Garlic | — | Feb 27 to Mar 13 | Nov 1 to 15 |
| Onions | Dec 19 to Jan 30 | Mar 13 to 27 | — |
| Cucumbers | Apr 11 to 25 | May 9 to 23 | — |
| Pumpkins | Apr 11 to 25 | May 9 to 23 | — |
| Peppers | Feb 21 to Mar 21 | May 9 to 23 | — |
| Carrots | — | Mar 20 to Apr 10 | Aug 9 to 30 |
| Sweet Potatoes | — | May 27 to Jun 3 | — |
| Watermelons | Apr 4 to 18 | May 9 to 23 | — |
| Sweet Corn | — | Apr 10 to 24 | — |
| Green Beans | — | May 9 to 23 | — |
| Zucchini | Apr 11 to 25 | May 9 to 23 | — |
| Broccoli | Jan 23 to Feb 13 | Mar 13 to 27 | Aug 16 to Sep 13 |
| Peas | — | Feb 27 to Mar 13 | Aug 9 to 23 |
| Spinach | Feb 27 to Mar 6 | Apr 3 to 17 | Aug 23 to Sep 27 |
| Sunflowers | — | Apr 10 to May 1 | — |
| Zinnias | May 15 to 22 | Jun 12 to 26 | — |
| Tulips | — | — | Sep 20 to Nov 15 |
| Daffodils | — | — | Sep 20 to Nov 1 |
| Grass Seed | — | Feb 27 to Mar 13 | Sep 20 to Oct 4 |
Nearby cities
- Philadelphia, PA zone 7b, last frost Mar 30
- New Brunswick, NJ zone 7a, last frost Apr 15
- Camden, NJ zone 7b, last frost Apr 2
- Plainfield, NJ zone 7a, last frost Apr 11
- Perth Amboy, NJ zone 7b, last frost Apr 15
- Bethlehem, PA zone 7a, last frost Apr 20
Planting in New JerseyAbout zone 7bPrintable calendar for Trenton
Questions
When is the last frost in Trenton?
Around April 10 in a typical year, based on NOAA's 1991-2020 records for Trenton Mercer Co Airport. There is still a 1 in 10 chance of frost after April 25.
What planting zone is Trenton in?
USDA hardiness zone 7b (2023 map), with parts of the city in zone 7a. The zone tells you which perennials survive the winter; planting dates depend on frost dates instead.
When should I plant tomatoes in Trenton?
Start seeds indoors March 14 to 28 and set plants out May 9 to 23.
When is the first frost in Trenton?
Around November 1 in a typical year, and before October 15 about 1 year in 10.