What Do You Plant in March?

The days might be getting longer, but that doesn't mean winter is over for all of us. Fortunately, raised beds allow those of us still getting snow and frost to be able to work the soil in our beds much sooner than those with in-ground gardens.

March is the time for us to plant seeds in ground and start seeds indoors in preparation for upcoming warmer temperatures, if you haven't already done so.

Before you can know what you're able to plant in your area, you need to figure out which growing season you'll be in for the majority of the month. Follow these simple steps to name your growing season.

Step One: Chart Your Highs and Lows

It’s time to use the internet to become further acquainted with your climate.

Google the average high and low temperatures for your town, county, city, or zip code for the months of March and April. If you’re in the United States, U.S. Climate Data is a helpful website that’s easy to use. Otherwise, you can search RSS Weather.

Step Two: Define Your Season

Rather than your garden zone, the goal is to understand your particular growing seasons. Once you know your seasons, you’ll have a better idea of what’s possible when in your unique garden, and to understand your seasons, all you need to know is the general weather for each month of the year in your area.  

Here in the Chicago area, we're transitioning between our cold and cool seasons. That means I've typically already started my cool season seeds indoors by now (around Valentine's Day).

Here's a breakdown of the different growing seasons:

• Cold Season - Average high temperature below 30°F (-1°C); guaranteed chance of frost/snow
• Cool Season - Average high temperature between 31°F and 64°F; likely chance of frost/snow
• Warm Season - Average high temperature between 65°F and 85°F (18.3°C and 29.4°C); no chance of frost/snow
• Hot Season - Average high temperature of 85°F (29.4°C) or above; no chance of anything close to cold

Now that you know your current growing season, all you have to do is figure out which plants like to grow in your season. Since March is often a time of transition into the upcoming growing season, we're going to begin preparing to grow things in our upcoming season.

Choose plants that will grow and produce within the time you have left in your current growing season, or if you're nearing the end of your season, begin planting in anticipation of your upcoming growing season.

I'm currently in my cold season, but I'm already preparing for my cool season.

For small plants, we can begin to direct seed them in the garden. For large plants, we can start them indoors or buy starter plants from a local nursery or garden center. Here's our guide to knowing when to start seeds indoors and which seeds to prioritize.

Know Your Last Frost Date

You'll count back from your predicted last frost date to help you know what you can plant and when. Click here to find your last frost date in the US.

• By subtracting 120 days from your last frost date, you can determine the date when you can begin starting onions and leek seeds. In Chicago, that was January 9th. In Houston, by comparison, that was actually back in November.
• By subtracting 100 days from your last frost date, you can determine the date when you can begin starting kale, broccoli, and cabbage seeds. In Chicago, that's February 6th. In Houston, that was early December.
• By subtracting 45 days from your last frost date, you can determine when you can begin starting tomatoes, peppers, eggplant, and basil seeds. In Chicago, that's March 31st. In Houston, that was early January.

If any of that seems intimidating, don't worry. Keep reading for some recommendations based on your growing season in March.

What plants can you plant in colder areas in March?

Here's what you can buy, direct sow, and start from seed indoors this month for your cool season:

BUY

Larger plants from the Brassica family, such as kale, broccoli, and cauliflower, will have more time to grow and thrive in your cool season garden if you buy them as transplants from your local nursery or garden center now. Buying herbs is also a good idea so that you can maximize their time in the garden and begin cutting herbs immediately.

PLANT

You can plant spinach, carrots, mustard, cabbage, and lettuce varieties when your soil is workable.

START SEEDS

At the end of March (or about 45 days before your final frost date), it's time to start your seeds for medium and large warm season plants indoors. That includes tomatoes, peppers, eggplant, and basil.

What plants can you plant in warmer areas in March?

If you live somewhere with milder winters, you could be finishing up your cool season in March. That means it's time to plant for your upcoming warm season.

Here's what you can buy, direct sow, and start from seed indoors this month for your warm season:

BUY

If you haven't already started tomatoes, peppers, and eggplants indoors, it's best to buy these plants as starts from your local nursery. That way, you'll be able to plant them outside soon and maximize their time in the garden before it gets too hot outside for them to thrive.

PLANT

This month is the time to plant seeds for arugula, cucumbers, beans, squash, and zucchini outdoors, directly in your garden.

START SEEDS

Believe it or not, early March is actually the time to start seeds for your hot season garden indoors. Okra is a great plant that thrives in heat.

What to Plant Outdoors in March

COOL SEASON

• mustard
• kale
• cabbage
• broccoli
• cauliflower
• lettuce
• spinach
• carrots
• herbs (except basil)

WARM SEASON

• arugula
• cucumbers
• beans
• squash
• zucchini
• basil

what seeds to start indoors in March

COOL SEASON

• tomatoes
• eggplants
• peppers
• basil

WARM SEASON

• okra
• tomatillos
• large gourds
• large melons

What are the best flowers to plant in March?

Zinnia seeds, calendula seeds, strawflower seeds, and marigold seeds can be planted outdoors once your final threat of frost has passed, or you can start them inside now. Wait a few weeks after your last predicted frost to plant your nasturtium seeds.

If you're going to enjoy cool/cold weather for a while longer, you can buy frost-tolerant pansies, pink dianthus, and violas from the nursery and use them to add some bright color to your raised beds before it's time to add spring flowers.

No matter what you plant, give your seeds a really good watering in and keep them moist in the first seven to ten days after sowing to prevent them from drying out. If you're new to starting seeds, check out our comprehensive video tutorials on seed starting in our membership program, Gardenary 365. You'll learn what supplies you need, how to prevent your seedlings from getting leggy, the best method to water your seedlings, and more.

If you're still getting your kitchen garden set up, learn more through Gardenary's many resources:

• Order a custom garden design through our virtual garden design service.
• Receive DIY help and planting plans through our online video course program: Kitchen Garden Academy.
• Get started with my book, Kitchen Garden Revival.

Another great resource to help you know what to plant when in your area is the nearest garden consultant to you. Find a Garden Consultant near you in our Directory. Follow them on social media or sign up for their newsletter for an easy way to know what's possible to grow in your area each month.

Whatever you grow in your garden, don't grow alone! We're here to help you have confidence and find success in the garden every step of the way, rain or shine or frost.

Here's to maximizing your growing time this March in preparation for a wonderful spring!