What Grows in Sun Valley Lake, Iowa

The last hard freeze (28°F) in Sun Valley Lake typically lands around Apr 12, per NOAA 1991–2020 climate normals — earlier than the light-frost dates most charts quote. That marks the hard freeze, not the last light frost — lighter frosts keep biting past it, which is why tender transplants here wait until about May 3.

The first hard freeze (28°F) in Sun Valley Lake typically arrives around Oct 25, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 11, so the watching starts about Sep 25 — about 196 days after the spring freeze cleared.

Measured between 28°F hard freezes, Sun Valley Lake sees about 196 frost-free days — roughly Apr 12 through Oct 25, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 3 to Oct 11, about 161 days.

The federal record around Sun Valley Lake is light — 19 documented sites across the 9 federal source types we checked, mostly Underground Storage Tanks entries (10), the nearest Underground Storage Tanks record about 0.4 miles out — and proximity to a documented site is information, not a diagnosis of any one yard. Growing food here starts from a strong position; a soil test before new food beds settles any site-specific question.

From about Sep 25 the job here turns from planting to protecting — the last start even a 30-day crop can finish. As the season closes around the first 28°F hard freeze near Oct 25 (NOAA 1991–2020 climate normals), three moves buy time: row cover or an old sheet over tender plants on still, clear nights; water the soil the afternoon before a freeze, so it holds warmth overnight; and harvest tomatoes, peppers and basil before Oct 25. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.