Summer squash gives you nothing for weeks, then more than a household can eat, and it will not keep. Most plants start producing in July in South Dakota, and the refrigerator holds the fruit for about a week. A surplus belongs in the freezer, in a neighbor’s kitchen, or in a pickle jar. Here is how to time the picking and what to do with the pile.
When summer squash are ready in South Dakota
Pick summer squash while the fruit is still small and the skin is glossy enough to dent with a thumbnail. For seed sown after the last frost, that usually means July. Clemson Cooperative Extension puts first harvest at about 55 days after planting, and for a direct-sown squash that count starts the day the seed goes into the ground.
Frost dates set the calendar. At the Sioux Falls airport weather station, NOAA’s 1991-2020 climate normals put the last spring freeze between April 29 and May 9 and the first fall freeze between September 24 and October 4. Those are reference-city numbers. Suburban and rural gardens usually freeze later in spring and earlier in fall, often by a week or two, and more at higher elevation. The state also spans USDA hardiness zones 3b to 5b (2023 map), so your own county can sit well away from the Sioux Falls dates. Your county South Dakota State University Extension office can tell you where your garden falls.
Count from June 1 and it is about July 26. That is the spread behind “July”: early sowings on warm ground come first, late or cool-soil sowings come weeks later.
Weather moves the pace after that. The reference station averages 13.8 days a year at 90°F or higher, so South Dakota summers are not relentlessly hot. Those hot days still matter, because a fruit that looked small on Monday can be oversized by the weekend. Rain is the other lever. June through August brings about 10.8 inches at the reference station, with June at 4.23, July at 3.25 and August at 3.34. July is the driest month, right when plants are carrying the most fruit. How far that rain goes depends on your soil. Sand lets it through within the day, clay holds it for a week, and a single thunderstorm in heat mostly runs off. A cheap rain gauge on your own plot settles the question better than any normal.
How often should you pick?
Every day or two in peak season. Once one fruit matures on the plant, the plant stops setting new ones, so picking often is what keeps it producing. Cut the stem with a knife or pruners and leave a short stub. A fruit that has already gone oversized still has uses (shredded for baking), but take it off right away.
If the fruit is scarred or hollowed before you get to it, see What Eats Summer Squash in South Dakota, and When. When a frost warning shows up in fall, pick everything the day before, including the small fruit. The full planting and care picture is in Growing Summer Squash in South Dakota.
Keeping them, and for how long
Summer squash does not store, and that is the whole answer. Clemson Cooperative Extension’s Home & Garden Information Center says to store it in a plastic bag in the refrigerator for up to 1 week. That is a ceiling under good conditions. A fruit picked a little too ripe, bruised, or left on the counter first will not make it that long.
Winter squash is a different crop. Butternut, acorn and the pumpkins cure a hard rind and keep for months in a cool room. Summer squash is picked with a tender rind and soft seeds, and that tenderness is what you are eating. It also means a cellar or a cool basement is not the plan for a bumper crop. The plan is the freezer, a jar, or someone else’s table.
What can you do with a glut of summer squash?
Freezing is the easiest route. Slice or cube young fruit, blanch it briefly, cool it quickly, drain it well and pack it in freezer bags with the air pressed out. Frozen squash goes soft when thawed, so it belongs in soups, casseroles, sauces and sautés, not on a grill. Shredded squash for baking can go in bags in measured portions. Drain off the water when you thaw it, or your bread will come out gummy.
For pickling, use a tested recipe. Plain summer squash is not recommended for home canning because the dense, low-acid flesh makes safe processing times hard to guarantee. Tested pickle and relish recipes with the right amount of vinegar are a different matter. SDSU Extension and the National Center for Home Food Preservation publish them.
Not everything has to go into storage. A bag of zucchini on a neighbor’s porch is a South Dakota summer tradition, and food pantries often take fresh garden produce, so call ahead to ask about drop-off hours. The best fix for a glut is the one you make in spring. A few plants feed most families, and the habit of picking small fruit makes a handful of plants go far. If you are still choosing what to sow, The Best Summer Squash to Grow in South Dakota covers the types worth the space.
Where in the house that actually is
The refrigerator is the only spot in most houses that gets close to what Clemson describes. A heated kitchen or pantry is too warm, and fruit left there softens and wrinkles within days. A garage swings with the weather, hot on a July afternoon, near freezing on an October night, and neither extreme suits a tender fruit. A basement is cooler than the kitchen in July, so it will do for a day or two while you plan dinner. It is not a place to hold squash for a week.
The fridge has its own catch. Domestic refrigerators run colder than some crops like, especially at the back wall and in the coldest shelf, and squash that is chilled too hard can develop pitted, watery patches. The crisper drawer is usually the gentlest spot. Keep the fruit in a plastic bag, off the back wall, and away from anything that sits against the cooling vents.
A thermometer settles it. Put an inexpensive fridge thermometer in the crisper drawer, leave it overnight and read it in the morning. Do the same on the shelf you were going to use. Compare both to the dial setting, which is only a rough guide. If you skip this check, you may lose a week of squash to a cold spot you did not know about, and you will not find out until the bag is full of slime.
If the fridge is full of other produce during peak season, give the squash its own bag, so moisture from one cut fruit does not spoil the rest. Do not wash it until you are ready to cook. Wet skin invites rot inside the bag.
Common questions
How big should summer squash be when I pick it?
Small. A zucchini is best around the length of your hand, and round or flat types like pattypan are best about a palm wide. Skin should be glossy and easy to dent with a thumbnail. Dull, hard skin means the seeds have toughened and the plant has likely stopped setting new fruit.
Can I leave summer squash on the counter?
For a day or so before cooking, yes. Beyond that, move it to the refrigerator in a plastic bag. The week-long limit applies to the refrigerator, and counter-stored fruit will not last as long.
When does the harvest end in South Dakota?
When frost kills the plants. The reference station’s first fall freeze falls between September 24 and October 4, but rural and suburban gardens often freeze a week or two sooner. Watch the forecast, and if a freeze is coming, pick every fruit the day before.
Can I freeze summer squash without blanching?
Shredded squash for baking can go into freezer bags raw and does fine. Sliced or cubed squash should be blanched first so it keeps its color and texture. Your county extension office can give you current timing for blanching.