June Seed-Starting Vegetables & Planting Guide

June is a busy month in the garden, marked by rapid growth and long, warm days. Warm-season vegetables are maturing, and now is the time for successive sowings to maintain a continuous harvest. Summer crops like beans, squash, cucumbers, and melons are going in the ground or being transplanted, while heat-loving herbs and perennials flourish. Proper irrigation, mulching, and pest monitoring become critical as temperatures climb, and careful thinning ensures vigorous growth for a productive summer garden.

Table of Contents

Zone-by-Zone Seed-Starting Guide for June

Listed by USDA Plant Hardiness Zones, warmest to coldest:

Zone 11

(Where the annual low temperatures stay above 40°F / 4°C.)

Direct-sow heat-loving vegetables and herbs.
Plant successive crops of beans, okra, cucumbers, squash, and melons.
Start sweet potatoes, yard-long beans, and roselle.
Transplant tomatoes, peppers, and eggplant for late summer harvests.
Mulch heavily to reduce soil temperature and conserve moisture.
Provide shade cloth for young seedlings during extreme heat.
Water deeply and consistently.
Remove bolted or declining spring crops.

Zone 10

(Where the annual low temperatures can reach 30°F / -1°C.)

Direct-sow warm-season vegetables for late-summer harvests.
Continue sowing beans, cowpeas, cucumbers, and summer squash.
Plant heat-tolerant herbs such as basil and Thai basil.
Avoid planting cool-season crops until late summer.
Mulch beds to conserve moisture.
Provide afternoon shade for tender seedlings.
Monitor irrigation closely.
Remove spent early crops.

Zone 9

(Where the annual low temperatures can reach 20°F / -7°C.)

Finish planting warm-season vegetables.
Direct-sow beans, cucumbers, squash, pumpkins, and melons.
Continue successive sowings of bush beans and sweet corn.
Transplant basil, sweet potatoes, and summer herbs.
Mulch beds to keep soil cool.
Stake and tie tomatoes as they grow.
Feed heavy feeders regularly.
Remove remaining cool-season crops.

Zone 8

(Where the annual low temperatures can reach 10°F / -12°C.)

Plant remaining tomatoes, peppers, and eggplant early in the month.
Direct-sow beans, corn, squash, cucumbers, pumpkins, and melons.
Continue sowing basil, dill, and parsley for late-season harvest.
Begin sowing heat-tolerant greens for succession.
Thin seedlings to final spacing.
Mulch beds to conserve moisture and suppress weeds.
Train vining crops onto supports.
Water deeply during dry periods.

Zone 7

(Where the annual low temperatures can reach 0°F / -18°C.)

Complete transplanting of warm-season crops.
Direct-sow beans, squash, cucumbers, corn, and melons.
Continue successive sowings of bush beans.
Begin sowing carrots, beets, and chard for later harvest.
Mulch beds once soil is warm.
Install trellises and supports for vining crops.
Monitor for pests as temperatures rise.
Water deeply and consistently.

Zone 6

(Where the annual low temperatures can reach -10°F / -23°C.)

Finish planting tomatoes, peppers, and eggplant early in the month.
Direct-sow beans, squash, cucumbers, and corn after frost danger has passed.
Continue sowing carrots, beets, and leafy greens.
Mulch beds after soil warms.
Thin seedlings of earlier sowings.
Stake tomatoes and install supports.
Use row cover early in the month if cool nights persist.
Begin regular feeding of fast-growing crops.

Zone 5

(Where the annual low temperatures can reach -20°F / -29°C.)

Direct-sow bush beans and summer squash early in the month.
Begin sowing carrots, beets, turnips, and rutabagas for fall harvest.
Start fall brassicas indoors.
Sow lettuce and spinach in cooler, shaded areas late in the month.
Mulch beds well.
Water deeply during dry periods.
Remove declining early-season crops.

Zone 4

(Where the annual low temperatures can reach -30°F / -34°C.)

Direct-sow bush beans early in the month.
Begin sowing carrots, beets, turnips, and chard for fall.
Start broccoli, cabbage, and kale indoors for transplanting.
Sow fast-maturing greens late in the month.
Mulch beds to conserve warmth and moisture.
Monitor weather closely.
Keep seedbeds evenly watered.

Zone 3

(Where the annual low temperatures can reach -40°F / -40°C.)

Limit sowing to the fastest-maturing crops.
Direct-sow bush beans early in the month.
Sow carrots, beets, and turnips for fall harvest.
Start hardy greens such as kale and mustard.
Use row cover or cold frames to extend the season.
Water consistently during dry periods.
Plan succession sowings carefully to maximize the short growing season.

June Fall Transition: Looking Ahead

As June winds down, the garden begins shifting from the first flush of summer growth toward planning for late summer and fall harvests. While warm-season crops are still producing, it’s the perfect time to sow heat-tolerant greens, successive beans, and fast-maturing fall vegetables in shaded or protected areas. Mulching, consistent watering, and careful thinning will keep plants vigorous through the hottest weeks, while early preparation of fall beds ensures a smooth transition to cooler-season crops. By tending both current and future plantings now, you set your garden up for a productive late-summer and early-fall harvest.