Growing potatoes in Iowa can be a rewarding experience. The state’s rich, loamy soil and humid climate are ideal for growing potatoes, and there are plenty of varieties to choose from. As a cool-season crop, potatoes are generally planted in early spring, when the soil is still cool but beginning to warm up.
For best results, potatoes should be planted in full sun and well-drained soil that is rich in organic matter. Raised beds or ridges can also be used to help improve drainage. Potatoes should be watered regularly and mulched to help keep the soil temperature and moisture levels even. With proper care and attention, you can expect a bumper crop of potatoes come harvest time.
Iowa’s Hardiness Zones And Climate
Zone 4 has the coldest climate of the four zones, with average winter temperatures ranging from -15 to -20 degrees Fahrenheit. Summers are warm, with temperatures ranging from 50 to 70 degrees Fahrenheit. Winters are long and snowy, with the average snowfall being approximately 40 inches per year.
Zone 5 is slightly warmer than Zone 4, with average winter temperatures ranging from -10 to -15 degrees Fahrenheit. Summers are mild, with temperatures ranging from 60 to 80 degrees Fahrenheit. Snowfall is around 35 inches per year.
Zone 6 has warmer temperatures than the other two zones, with average winter temperatures ranging from 0 to -10 degrees Fahrenheit. Summers are usually hot, with temperatures ranging from 70 to 90 degrees Fahrenheit. Snowfall is around 25 inches per year.
Zone 7 has the warmest climate of the four zones, with average winter temperatures ranging from 10 to 20 degrees Fahrenheit. Summers are very hot, with temperatures ranging from 80 to 100 degrees Fahrenheit. Snowfall is around 15 inches per year.
Different varieties of seed potatoes
When selecting seed potatoes for growing in Iowa, it is important to be mindful of the variety’s days to harvest and the length of time you have before you want to harvest them.
Early-season varieties such as ‘Yukon Gold’ and ‘Red Norland’ have fewer days to harvest and should be planted as soon as possible for harvesting in late summer.
Mid-season varieties such as ‘Russet Burbank’ and ‘Kennebec’ have more days to harvest and should be planted in late April or early May for harvesting in fall.
Late-season varieties such as ‘Cara Russet’ and ‘All Blue’ have the most days to harvest and should be planted in late April or early May for harvesting in early winter. Be sure to select varieties with the right number of days to harvest for your intended harvest date. Some good potato varieties for Iowa include:
- Russet Potatoes: 85-95 days
- Yukon Gold Potatoes: 90-110 days
- Red Potatoes: 80-90 days
- Purple Potatoes: 90-110 days
- Fingerling Potatoes: 90-120 days
- Sweet Potatoes: 90-120 days
- White Potatoes: 90-100 days
- All-Blue Potatoes: 95-105 days
- Yellow Finn Potatoes: 85-95 days
- Kennebec Potatoes: 85-95 days
When To Plant Potatoes In Iowa
In Iowa, potatoes should be planted in late March or early April. This is when the soil temperature is typically around 40-50°F and the risk of frost has passed. Planting too early may result in poor emergence, while planting too late may lead to reduced yields. Planting dates for potatoes in Iowa are:
- Zone 4: Around April 30th
- Zone 5: Around April 15th
- Zone 6: Around April 7th
- Zone 7: Around March 24th
How To Plant Potatoes In Iowa
Begin the planting process for seed potatoes by tilling the soil to a depth of 8 inches and incorporating organic compost. Once you have done this, find a sunny location that receives at least 8 hours of direct sunlight and place the seed potatoes.
Plant the seed potatoes with the “eyes” facing upward, leaving a distance of 8 to 10 inches in between each. Cover the seed potatoes with a layer of soil that is 3-4 inches thick, and make sure to water them adequately. As the potatoes start to sprout, add more soil to the rows to keep them adequately buried.
Water the potatoes on a regular basis and remove any weeds from the area. For those living in hot and dry climates, you may want to cover the soil around the potatoes with straw, although this is not essential.
Caring For Potato Plants
Caring for potato plants is pretty easy – they’re incredibly hardy and generally no-fuss. Potato plants need full sun and well-drained soil to thrive. They should be watered deeply and regularly, allowing the soil to dry out between waterings.
Fertilizing is also important for optimal growth. Potato plants need a balanced fertilizer with equal parts nitrogen, phosphorus, and potassium. This should be applied every four to six weeks, depending on the soil’s nutrient content.
It is also important to keep the soil evenly moist, as potatoes do not tolerate dry or waterlogged conditions. Mulching around the potato plants can help retain moisture and reduce weeds.
When To Harvest Potatoes In Iowa
There are two sure ways to know your potatoes are about ready to harvest! The first is counting backward from your current date to their planting date. Potato varieties have an approximate number of days to harvest, so consult the days to harvest for the particular variety of potatoes you’ve planted. If you aren’t sure, assume it’s around 100 days.
The appearance of your potato plants is another dead giveaway. You will know your potatoes are ready to harvest when the foliage begins to turn yellow and die back. Your plants will go through an entire flowering cycle, which is nice because the flowers are really beautiful.
Allow the soil around the plants to dry before harvesting, but don’t allow it to be dry for too long. Once harvested, inspect the potatoes carefully- they should be firm and free of green or soft spots.
Carefully dig up the potatoes with a garden fork, taking care not to damage the potatoes in the process. Once the potatoes have all been dug up, brush off any excess soil and inspect them for any damage. Discard any potatoes that are damaged, as these are not suitable for long-term storage.
Finally, gently place the potatoes in a cool, dry, and dark area for storage. It is important to only store undamaged potatoes, as damaged potatoes can quickly rot.
