Planting guide

What to plant in Zone 4 in June

USDA Zone 4 · US Northern Hemisphere June

June is warm-season planting month in zone 4. The average last freeze was around May 7 to 10 at NOAA's stations in Fargo, Bismarck, Helena and Caribou, Maine, and the late freeze that comes one year in ten has passed by May 23 to 25, so the crops that need two frost-free weeks and warm nights go out now. The season is short: the average first fall freeze at the same stations is September 30 or October 1, about 143 to 147 days after the last spring one.

Plant now

Pepper and eggplant transplants

Very tender: at least two weeks after the last frost and nights of 60-65°F (16-18°C). Early June at the stations above.

Cucumbers, summer squash and zucchini

Set out transplants or sow directly once the soil has warmed to 70°F (21°C).

Melons, winter squash and pumpkins (first half of the month)

They need most of what is left of the season. K-State lists 80 to 105 days to first harvest for winter squash and 85 to 130 for pumpkins, so pick the shorter end and plant early in the month.

Tomato transplants (if not out yet)

K-State lists 52 to 120 days to first harvest. Pick from the short end: the first fall freeze averages the end of September.

Bush beans and sweet corn

Sow now, and sow beans again later in the month for a longer harvest. K-State lists 68 to 90 days for sweet corn, so a sowing after mid-June may not finish before the first freeze.

Basil

Safe two weeks after the last frost, so it goes out with the peppers.

Timing notes

  • Count the days. One year in ten the first fall freeze comes by September 16 to 18 at these stations. Add a crop's days to harvest to its planting date and make sure it lands before then.
  • The fall garden starts sooner than it feels like it should. Purdue Extension's rule is to plant cool-season crops at least four to eight weeks before the first fall frost, which puts fall broccoli, kale, lettuce and spinach in the ground in August here, or late July to be safe.
  • Look up the average last frost for your own town with the frost date calculator; the zone number is a winter-minimum band, not a planting date.
Frost dates and a seed-starting schedule for your ZIP code Free calculator from NOAA station records: last spring frost, first fall frost, and what to start each week. ← All planting guides