What to plant this week in Sioux Falls, SD
Sioux Falls gardeners should brace for potential late spring freezes around May 8, as the average last frost date remains a critical threshold this week. While you can safely sow Zucchini and Yellow Summer Squash now after a soil warm-up, be ready to cover tender seedlings if temperatures dip toward -20°F in hardy spots or fluctuate above ground zero.
The next 7 days
Sioux Falls, SDGrowing in Sioux Falls right now
- Sioux Falls' clay-heavy loam soils tend to stay cool longer than surrounding areas; wait until the top 6 inches feel warm before planting your Zucchini and Yellow Summer Squash seeds.
- The region's semi-arid climate means rainfall is often sporadic this season, so check drainage in low-lying parts of town where standing water can rot squash roots after a sudden spring shower.
- With an average first frost on Oct 8, focus this week on preparing your harvest schedule for early crops like Beet and Carrot to pull before the ground freezes solid.
Sow this week
2 crops- Yellow Summer Squash
- Zucchini
Transplant this week
Nothing is due to go out this week.
Harvest soon
55 crops- Bachelor's Button (Cornflower)
- Banana Pepper
- Basil
- Beet
- Bell Pepper
- Borage
- Bush Bean
- Cabbage
- Carrot
- Cauliflower
- Cherry Tomato
- Cleome (Spider Flower)
- Collard Greens
- Cosmos
- Cowpea (Black-Eyed Pea)
- Cucumber
- Dill
- Eggplant
- Fava (Broad) Bean
- Fennel
- French Marigold
- Garden Geranium (Zonal)
- Garden Verbena
- Garlic
- Ground Cherry
- Jalapeño
- Lantana
- Lima Bean
- Napa Cabbage
- Nasturtium
- Onion
- Ornamental Sweet Potato Vine
- Parsley
- Petunia
- Poblano Pepper
- Pole Bean
- Potato
- Roma Tomato
- Rutabaga
- Scallion (Bunching Onion)
- Scarlet Runner Bean
- Shallot
- Shishito Pepper
- Shiso (Japanese Basil)
- Snapdragon
- Summer Savory
- Sunflower
- Sweet Corn
- Swiss Chard
- Thai Basil
- Tomato
- Vinca (Madagascar Periwinkle)
- Yellow Summer Squash
- Zinnia
- Zucchini
Seasonal tips
- Start succession sowing bush beans and snapdragons every two weeks for a continuous harvest.
- Deadhead Cosmos and Cleome regularly to encourage more blooms throughout the summer.
- Thin out carrot and beet seedlings now to give remaining plants enough room to mature.
Pest & disease watch
- Watch for late-season slugs hiding in mulch near young Zucchini plants, as moisture from occasional rain showers brings them out.
- Monitor for aphids on newly transplanted herbs like Basil and Parsley, which can stress quickly if exposed to wind chills before the frost date passes.
Watering this week
Water deeply in the morning to keep roots cool and reduce evaporation during this hot season.
Harvest your first ripe cherry tomatoes today to enjoy their peak flavor while they are young and tender.
Sioux Falls gardening questions
3Can I plant my summer squash now in Sioux Falls without waiting for the frost?
Yes, you can sow Yellow Summer Squash and Zucchini right now as long as the soil has warmed up after a few days of above-freezing weather. Cover them with a row cloth temporarily if a cold snap threatens before your average last frost date of May 8.
My Basil and Tomato seedlings are struggling; is this normal for our climate?
It can be, as Sioux Falls' clay soil retains moisture unevenly and sudden wind shifts can cool the air quickly despite being in Zone 5a. Ensure pots have drainage holes to prevent root rot, and consider using a cold frame at night until past May 8.
When should I start pulling my early Carrots and Beets before winter?
Start harvesting your Beet and Carrot crops soon, as the ground can freeze hard by late October with an average first frost around Oct 8. Pulling them while the soil is still slightly moist but unfrozen will keep the roots sweeter.
Other cities in zone 5a
6See the full zone 5a guide → · Plan your Sioux Falls garden in SproutGuide →