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A golden ground cherry in its open papery husk
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When to plant ground cherries in Walla Walla, WA

Start ground cherries from seed indoors Mar 13–27, then plant the young plants in the garden in Walla Walla May 1–29.

Easy Plant young plants (starts)

Difficulty
Easy
Sun
Full sun
Spacing
2 to 3 feet apart
Planting depth
Bury the stem up to the first leaves, like tomatoes
Frost
Killed by frost
First harvest
About 70 days after planting

Why these dates

Walla Walla's typical last spring frost is March 27. Frost kills ground cherries, and warm-season crops also need warm soil. Soil here stays cold for weeks after the last frost, so planting waits until about May 1.

Columbia Basin and low eastern valleys. Hot, dry summers and quick spring warm-up. Warm crops go in earlier than west of the Cascades, and irrigation matters more than rain.

How to grow ground cherries in Walla Walla

  1. Start seeds indoors Mar 13–27 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 1–29, 2 to 3 feet apart. Bury the stem up to the first leaves, like tomatoes.
  4. Water deeply once or twice a week rather than a little every day, and mulch once the soil is warm.
  5. Harvest: Gather the fruit after it drops to the ground in its husk, when the husk is dry and tan and the fruit inside is golden. Rake or shake the plants every few days.

Key numbers

Growing notes

What makes the difference in Northwest gardens, in plain language.

What ground cherries are

Ground cherries are small relatives of tomatillos and tomatoes. Each marble-sized golden fruit grows in a papery husk and tastes like a mix of pineapple and tomato. Unlike tomatillos, a single plant pollinates itself, so one or two plants are enough.

They ripen earlier and more reliably than most tomatoes, which makes them a good bet for cool west-side and coastal summers.

Growing and picking

Start seeds indoors about seven weeks before planting out, and plant them in warm soil after the last frost, buried a little deeper than they grew in the pot. They're low, sprawling plants, so give them room and skip the cage. Average soil is fine; too much nitrogen gives leaves instead of fruit.

The fruit drops to the ground when it's ready. Collect it every few days. Fruit in dry husks keeps for several weeks at room temperature.

Volunteers next year

Fruit you miss drops seed, and seedlings will pop up in that bed next year. Pull the extras or move a few to where you want them. Like tomatoes, don't grow them where tomatoes, peppers, eggplants or potatoes grew last year.

Common questions

When is the last frost in Walla Walla, WA?

Typically March 27. In 9 years out of 10, frost is over by April 22. These are 1991–2020 NOAA climate normals for Walla Walla Regional Airport.

Is it too late to plant ground cherries in Walla Walla?

The spring planting window runs through May 29. Later plantings may not have time to produce before the first fall frost, which usually arrives around October 31.

When should I start ground cherries from seed indoors in Walla Walla?

March 13 to March 27, which is 7 to 5 weeks before the May 1 planting date. Or buy young plants at a garden center instead.

Are ground cherries the same as tomatillos?

They're close relatives, but ground cherries are smaller, sweeter and self-pollinating. Tomatillos are tart and need two plants to set fruit.

Are green ground cherries safe to eat?

No. Eat only fully golden fruit. Unripe fruit, leaves and husks contain compounds that can upset your stomach.

How do I know they're ripe?

They fall off the plant. The husk turns dry and tan, and the fruit inside is golden yellow.

Also plant in Walla Walla around the same time

Planting dates for ground cherries in nearby areas

Full planting calendar for Walla Walla · Ground cherries in every city