The State of Iowa spans parts of gardening Zones 4 (northeast Iowa) through 7 (southwest Iowa), which means the planting dates vary slightly throughout the state. Most of the regions in Iowa have a medium growing length, which gives you a good amount of time to start your vegetables and reap a bountiful harvest.
With that being said, there are some differences between regions you should know about. Let’s look at them closer.
When to Get Started
Starting times can vary per zone, which means you should pay attention to when your first and last frost dates are (more on this below). A simple Google search will help you determine what region you’re in, when the frost dates are, and what you should do in your specific zone to make the most of your growing time.
To save you some research, we’d like to touch on each of the gardening zones in Iowa:
Zone 4 – This zone has a shorter growing season than the others, which means you should choose vegetable varieties that have faster maturing dates. With a last frost date of June 1st and a first frost date of October 1st, your planting and harvesting time is cut down. One of the best things zone 4 gardeners can do is start their seedlings indoors to capitalize on growing time.
Zone 5 – This zone has a medium length growing season. You should have no problem getting most vegetable varieties to mature before your first frost date in this zone. Because Zone 5 has a last frost date of May 15h and first frost date of October 15th, it’s important to keep an eye on the weather before you start your spring planting. A safe bet is to start with broccoli, carrots, onions, kale, peas, and beets in the spring.
Zone 6 – The sixth gardening zone also has a medium length growing season, but is a little longer than zone 5. Most of the vegetable varieties you can grow here will mature before your first frost date. Typically, zone 6 has a last frost date of May 1st and a first frost date of November 1st, giving you ample time to plant, grow, and harvest. As with all zones, the dates may vary a week or two, so pay attention to the weather before you start planting.
Zone 7 – The extreme southwestern parts of Iowa have the best growing time. Zone 7 has a last frost date of April 15th and a first frost date of November 1st. As a result, most vegetable varieties will mature before the first frost date in this zone.
What to Work On
Every growing season starts with healthy soil. No matter what gardening region you’re located in, you should take some time to prep your soil. If your garden has been running for a few years, take the opportunity this year to complete a soil test. Year after year your garden’s nutrients get depleted by the vegetables you grow, so you may have to add compost or organic fertilizer to rebalance the pH level. You should also determine what vegetable varieties you want to grow this year so you can start them indoors as soon as you can.