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When to plant melons in Winthrop and Twisp, WA

Plant melons in the garden in Winthrop and Twisp May 20 – Jun 10, either as seeds or as young plants started indoors Apr 22–29.

Tricky here Plant seeds or young plants

Why these dates

Winthrop and Twisp's typical last spring frost is May 15. Frost kills melons, so planting starts once frost risk drops, around May 20. Keep row cover or a frost blanket handy for the first couple of weeks, since a late frost is still possible.

Inland Northwest. Higher, colder interior valleys. Cold springs and an earlier fall mean a shorter season; quick-maturing varieties pay off.

Difficulty
Tricky here
Sun
Full sun; the hottest spot you have
Spacing
24 to 36 inches apart
Planting depth
1 inch deep
Frost
Killed by frost
First harvest
About 85 days after planting

Step by step

  1. Start seeds indoors Apr 22–29 in trays or small pots under a grow light or in your sunniest window. Or skip this step and buy young plants (starts) at a garden center.
  2. Harden off the young plants: about a week before planting, set them outside for a few hours a day, a little longer each day.
  3. Plant them in the garden May 20 – Jun 10, 24 to 36 inches apart. If you plant seeds instead, sow them 1 inch deep.
  4. Water deeply once or twice a week rather than a little every day, and mulch once the soil is warm.
  5. Harvest: Cantaloupes are ripe when the stem slips off with a gentle push. Watermelons are ready when the curly tendril nearest the fruit turns brown and dry.

Varieties that do well here

  • Sugar Baby (watermelon)
  • Minnesota Midget (cantaloupe)
  • Halona (cantaloupe)

Watch out for

Cool soil and cool nights are the main obstacle west of the Cascades. Black plastic mulch and row cover until flowering make the difference.

The toughest heat lover for west-side gardens: choose short-season varieties and use black plastic and row cover. Eastern valleys grow them easily.

Common questions

When is the last frost in Winthrop and Twisp, WA?

Typically May 15. In 9 years out of 10, frost is over by June 1. These are 1991–2020 NOAA climate normals for Winthrop.

Is it too late to plant melons in Winthrop and Twisp?

The spring planting window runs through June 10. Later plantings may not have time to produce before the first fall frost, which usually arrives around September 22.

When should I start melons from seed indoors in Winthrop and Twisp?

April 22 to April 29, which is 4 to 3 weeks before the May 20 planting date. Or buy young plants at a garden center instead.

Also plant in Winthrop and Twisp around the same time

Planting dates for melons in nearby areas

Full planting calendar for Winthrop and Twisp · Melons in every city