Grow the Food You Grew Up With: A US Planting Guide to Global Heirloom Vegetables

Can you grow international vegetables in the United States?

Yes. Every crop in this guide grows in most of the continental US, because the US spans the same conditions these vegetables evolved in, from short cool summers in zones 3 to 5 to nearly frost-free heat in zones 9 to 11.

The key is matching the crop to your frost dates, not your state. Heat-lovers like bitter melon and okra need 60 to 90 warm days after last frost, while cool-season crops like bok choy grow better in a Minnesota spring than in a Gulf Coast summer. Check what to plant right now for your ZIP code before choosing varieties.

Mexican and Central American kitchen crops

Tomatillos: plant two or more plants, they need a partner to pollinate, 3 feet apart, after last frost. They are ready to pick when the fruit fills its papery husk, about 75 to 85 days. Treat them like a tougher, more forgiving tomato: same sun, same soil, fewer pests. One pair of plants yields 100 or more fruits, enough for a year of canned salsa verde. Try Purple de Milpa, an heirloom on the sweeter side, or the classic Toma Verde. Cold-climate note: tomatillos ripen faster than most tomatoes, so they succeed in zones 4 and 5 where big slicers struggle.

Epazote, the herb that makes a pot of beans taste right, grows like a weed from seed in any sunny spot; keep it in a container unless you want it everywhere.

Mexican sour gherkins, also called cucamelons, are grape-sized cucumbers with built-in lime tang. One trellised vine produces for months and shrugs off the cucumber beetles that destroy standard cukes.

East and Southeast Asian staples

Bok choy: sow directly in the garden 4 weeks before your last frost, or in late summer for fall. It is a 30 to 45 day crop that prefers cool weather and bolts in heat. Space baby varieties 6 inches apart, full-size 10 inches. It is one of the fastest food crops you can grow, and it thrives in containers as shallow as 8 inches, which makes it ideal for balcony and container gardens. For summer harvests choose bolt-resistant Joi Choi; for speed, Shanghai Green baby bok choy.

Bitter melon needs real heat. Transplant after nights stay above 60°F, give it a 6-foot trellis, and expect fruit in 55 to 70 warm days. Soak the hard seeds for 24 hours before starting them indoors. In zones 7 and up, direct sowing works; in zones 4 to 6, start indoors 4 weeks early and use a short-season variety like India Baby. Pick fruits young and green. Pale, swollen fruit is past its prime and truly bitter.

Shiso, also called perilla, self-seeds like mint and handles part shade; one packet is a lifetime supply. Thai basil grows exactly like sweet basil but holds its licorice flavor through cooking. Yardlong beans out-produce standard pole beans in hot, humid summers where regular beans quit. Give them an 8-foot trellis and pick pods at pencil thickness.

South Asian and Caribbean crops

Callaloo is vegetable amaranth, and it grows almost anywhere in the US as a heat-loving summer green. Sow after last frost and start cutting leaves in 30 to 40 days. Where spinach bolts by June, callaloo is just getting started. The same plant feeds Caribbean, Nigerian, and Indian kitchens under different names: callaloo, efo tete, chaulai. Cut-and-come-again harvesting keeps one 4-foot row producing all summer. Note for Caribbean cooks: if your family's callaloo is dasheen, meaning taro leaves, amaranth is the temperate-garden stand-in; true taro needs zones 8 and up.

Okra is an African heirloom that anchors Southern, Indian, and Caribbean cooking, and modern short-season varieties fruit in 50 to 55 days, putting it in reach of zone 4 and 5 gardens. Sow after soil hits 65°F, or start in paper pots since it hates root disturbance. Pick pods at 3 inches, every other day, or the plant stops producing; a good week yields more than you can eat fresh, which is what pickled okra is for. Northern gardeners: choose Jambalaya or Clemson Spineless 80. Heirloom hunters: Burgundy or the Louisiana classic Cow Horn.

Edamame grows like bush beans: sow thick after last frost and harvest the whole plant when pods are plump but still bright green. Daikon is a 60-day fall crop that also breaks up compacted soil for free. Bottle gourd, sold as lauki or opo, wants the same trellis-and-heat treatment as bitter melon and yields heavily in zones 6 and up.

Where do you buy international and heirloom seeds?

Look for seed companies that specialize in the cuisine you are growing. They carry true-to-type varieties and regional growing notes that big-box seed racks do not.

Well-regarded sources US gardeners use: Kitazawa Seed Co. for Asian vegetables, in business since 1917; Baker Creek for global heirlooms; Southern Exposure for Southern and African-American heirlooms; Native Seeds/SEARCH for Southwestern and Mexican landraces; and Second Generation Seeds, Asian-American grown.

Local seed libraries and cultural community gardens are also gold mines, and those seeds are already adapted to your area.

Which global crops work in small spaces and containers?

Best for balconies and rentals: bok choy in an 8-inch pot, shiso in any pot, Thai basil in a 1-gallon, cucamelons in one trellised 5-gallon bucket, and callaloo in a window box, cut young.

Trellised vines like bitter melon, yardlong beans, and bottle gourd turn a single railing planter into serious production because they grow up, not out. That also puts the harvest at hand height, with no bending.