It’s time to bring your garden to life! Make sure you know what to plant in May to ensure a bountiful harvest all season long!

The Importance of Understanding Frost Dates

Understanding frost dates is an important factor in planning a successful garden. By planting at the appropriate time and selecting the right crops, you will maximize your chance of a bountiful and fruitful harvest.

Planting too early in regions with short growing seasons (typically zones 1-5), can be detrimental to the success of a garden. If plants are exposed to frost, they may become damaged or die, leading to wasted time, effort, and money. 

That’s why it’s important to wait until after the last frost date to plant sensitive crops such as tomatoes, peppers, and eggplants. As exciting as it is to get growing, by waiting until after the last frost, these plants will have the best chance of survival and success.

On the other hand, waiting too long to plant can also have negative consequences. Some plants, such as cool-season crops like lettuce and spinach, prefer cooler temperatures and will not do well in hot weather. Waiting until after the first frost date in the fall to plant these crops may result in stunted growth and reduced yield.

Frost Dates for Zone 5 Gardens

My area of Eastern Iowa has an average last frost date of May 15, and gardening gets really busy in May in Zone 5. The average last frost date is what determines the order of planting for your kitchen garden. If your last frost date is around May 15, this list is perfect for you.

If your last frost date is before or after mine, you will need to adjust accordingly. Not sure what gardening zone you live in? Use this handy tool to input your zip code and find out. This tool will tell you your hardiness zone and  last frost date based on your zip code.

Our growing season in a Zone 5 Garden typically starts in late March or early April, depending on weather conditions. By this time, hopefully, you’ve already planted cold-tolerant crops outdoors, including peas, lettuce, spinach, kale, potatoes, and radishes. 

Additionally, many gardeners in zone 5 have already started warm-season crops indoors in late winter or early spring, such as heat loving tomatoes, peppers, and eggplants, in order to get a head start on the growing season. 

Watch the Weather Before Planting in May

In a Zone 5 garden, from May 15 on, it’s time to start planting summer crops. But before you plant, make sure to look carefully at the long term weather forecast and make sure the risk of frost has passed. I can’t tell you how many times we’ve had a late frost on or after May 15. 

Before planting in May, you should make sure that the soil has warmed up sufficiently for planting. Warm weather crops prefer warm soil temperatures, so it’s important to wait until the soil has reached a consistent temperature of at least 60°F (15°C) before planting. 

We recommend this handy tool to make sure your soil is warm enough for planting warm weather crops. It will also tell you soil pH so you know what amendments to add to make your soil perfect for your summer and fall crops!

How to Protect Plants from Cold Temperatures

Remember, warm weather crops are sensitive to cold, and your temperatures drop too low after planting, you’ll need to protect them to prevent them from being damaged or killed.

Cover them

Covering the plants with a blanket, tarp, or row cover can provide some insulation and protect them from frost damage. Make sure the cover is securely anchored and doesn’t touch the plants, as contact with a cold cover can cause damage as well.

Use water

Water has a high heat capacity and can absorb and release heat slowly, making it a useful tool for protecting plants from frost. Watering the plants thoroughly before a frost can help keep them warmer by releasing heat as it freezes. You can also use a soaker hose or irrigation to create a layer of ice on the plants, which can provide insulation.

Move them

If possible, move the plants indoors or to a more protected location, such as a greenhouse or covered porch. This may not be practical for larger plants or for a large number of plants, but can be effective for smaller crops.

Plant in raised beds

Planting in raised beds can help warm the soil and provide better drainage, which can help protect plants from frost damage.

Use mulch

Applying a layer of mulch around the plants can help insulate the soil and protect the plants’ roots from cold temperatures.

How to Plant Your Garden

Once the weather is good, it’s time to plant! There are two ways to plant your garden in May: direct sow or planting seedlings. Here’s the difference.

What is Direct Sowing?

Direct sowing means you plant seeds directly in the ground where they will grow, without starting them indoors first. This method is typically used for crops that don’t transplant well or that mature quickly, such as radishes, beans, and peas. 

The main advantage of direct sowing is that it is simpler and less time-consuming than starting seedlings indoors, and can be more cost-effective since no equipment or supplies are needed.

Planting Seedlings

Planting seedlings, on the other hand, involves starting seeds indoors or purchasing established seedlings from a nursery and then transplanting them into the garden. 

Gardeners usually plant seedlings for crops that require a longer growing season, such as tomatoes, peppers, and eggplants. Seedlings can be started indoors several weeks before the last expected frost date, giving them a head start on the growing season. 

The main advantage of planting seedlings is that it allows gardeners to extend the growing season and get a jump start on producing a harvest.

What to Plant in May {Zone 5}

As long as soil temperatures are consistently around 50°F, you can plant the following vegetables in your garden before your last frost date. 

What to Plant in May BEFORE Last Frost Date in Zone 5

• Beans, after May 5, direct sow seeds
• Beets, anytime during May, direct sow seeds
• Cabbage, early May, plant seedlings
• Carrots, early May, direct sow seeds
• Lettuce, early May, direct sow seeds
• Potatoes, early May, plant seed potatoes using the no-dig method
• Radish, early May, direct sow seeds
• Sweet corn, early May {as long as it’s not too cold and rainy}, direct sow seeds

What to Plant in May AFTER Last Frost in Zone 5

• Cucumber, mid May, direct sow seeds
• Eggplant, mid May, plant seedlings
• Pepper, mid May, plant seedlings
• Pumpkins, mid May, direct sow seeds
• Squash, mid May, direct sow seeds
• Tomatoes, mid May, plant seedlings

When planting vegetables, make sure to choose a location that receives plenty of sunlight and has well-draining soil. 

Remember to water regularly and use organic fertilizer to promote healthy growth. Read this post on how to make your watering more eco-friendly.

Mulch is your friend, so make sure to mulch too! Read this post where to find free mulch!

What Flowers and Herbs Should be Planted in May

Hardy herbs and flowers

Hardy flowers and herbs are plants that are able to withstand cold temperatures and frost without being damaged. These plants can be planted in the garden as soon as the soil can be worked in the spring, which is usually around mid-April to early May in zone 5. 

• A few examples of hardy herbs include oregano, chives, thyme, and sage.
• A few examples of hardy flowers include yellow,  Black-eyed Susans, Coneflowers, and Shasta daisies.

Half-hardy herbs and flowers 

Half-hardy herbs and flowers are plants that can tolerate some cold temperatures, but will be harmed by frost.These plants can be planted outdoors after the last expected frost date.

• Examples of half-hardy herbs include basil, cilantro, parsley, and dill. 
• Types of half-hardy flowers include snapdragons and petunias.

Tender herbs and flowers

Tender herbs and flowers are plants that are not able to withstand frost or cold temperatures and are often grown as annuals in the garden. They should only be planted outdoors after all danger of frost has passed.

• Examples of tender herbs include basil, lemon verbena, and stevia.
• Types of tender flowers include marigolds and zinnias.

Don’t forget Companion Plants!

Companion planting is the practice of planting different plants together in the garden that benefit each other in some way. There are lots of benefits of companion planting, so make sure you add strategic companion plants as you plant your garden in May!

Pest control 

Some plants, like marigolds, have natural insect-repelling properties that can help keep pests away from nearby plants. Planting certain herbs, such as basil, can also help repel pests.

Improved soil health 

Certain plants, like legumes, can fix nitrogen in the soil, which can benefit nearby plants by providing them with a source of nutrients. Other plants, like sunflowers, have deep roots that can help break up compacted soil and improve drainage.

Increased yields

Planting certain crops together can help increase yields by promoting healthy growth and reducing competition for resources. For example, planting beans and corn together can benefit both crops, as the beans can fix nitrogen in the soil, which the corn can use as a nutrient source.

Improved flavor

Some companion plants, like herbs, can improve the flavor of nearby plants by repelling pests or providing a complementary flavor.

Attracting pollinators

Planting flowers that attract bees and other pollinators can help improve pollination and increase yields for nearby plants.

More Posts You May Like

What Vegetables to Plant in March + Early Spring Garden Chores

What to Plant in April + Printable Garden Planting Guide

June Gardening Chores

10 Practical Gardening Tips for New & Seasoned Gardeners

10 Effective Methods of Organic Pest Control

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