How Do You Know When to Plant?

When you get ready to start your first garden, one of your first questions might be “How do I know when to start my seeds?” Well, to answer that question, you need to know 1) what plants you want to grow, 2) when you want to eat them, and 3) if you’re going to grow them indoors or outside.

If you’re going to grow your plants indoors, you don’t need to worry about the growing season and you can start your seeds pretty much any time. However, if you’re growing outdoors, it’s a little more complicated. Then you need to learn about frost dates.

Figuring out your last frost date

If you’re starting your garden in the spring, the first thing to find out is the last frost date for your area of the world. For me, the likely last frost date (90% chance) is May 22nd but I usually use Memorial Day just to be safe.

Here’s a link that allows you to check for frost dates by zip code (https://garden.org/apps/frost-dates/).

So, depending on the kind of plant, whether it can be started indoors, and how long it takes to get transplant size, you can figure out when to plant your seeds indoors, or out. To make it easier for you though, I’ve provided a listing below of when you want to start or transplant different seeds and when you might expect your first harvests. Find your last frost date on the calendar and count backwards or forwards the right number of weeks to figure out when to start each type of seeds.

Note: The dates below are the earliest dates you could plant each type of seeds. You can shift your planting dates by a week or two depending on your schedule, the weather, or other factors. There are some cool weather plants (like spinach, salad greens, peas) that won’t sprout well if you wait too long and the weather gets too hot, but in general, treat these dates like a guideline more than an absolute rule. Don’t let the perfect be the enemy of the good, late is almost always better than never in the garden.

When to Plant Each Kind of Seeds

8 weeks before last frost

• Plant Outdoors: Spinach (if soil is workable)
• Plant Indoors: Nightshade family (tomatoes, eggplants, peppers), Brassica family (broccoli, brussel sprouts)

7 weeks before last frost

• Plant Outdoors: Peas (if soil is workable)

6 weeks before last frost

• Plant Outdoors: Brassica family (Kale, kohlrabi), salad greens, leeks, root vegetables (potatoes, radishes, turnips, onion sets)
• Transplant: Tomato sprouts with at least one set of true leaves into 4 inch pots

5 weeks before last frost

• Plant Outdoors: Beets, onion starts
• Plant Indoors: cabbage, cauliflower, parsley

4 weeks before last frost

• Plant Outdoors: Chard, lettuces
• Plant Indoors: Basil, pumpkins and squash

3 weeks before last frost

• Plant Outdoors: Carrots

2 weeks before last frost

• Plant Outdoors: Strawberry plants (bare root)

Last Frost Date

• Plant Outdoors: Beans, corn, cucumbers, pumpkins, squash, melons
• Transplant: Nightshade family (tomatoes, eggplants, peppers), melons, pumpkins, squash

1 week after last frost

• Start harvesting: Green onions

3 weeks after last frost

• Start harvesting: Spinach

4 weeks after last frost

• Start harvesting: Salad greens

6 weeks after last frost

• Start harvesting: Basil

7 weeks after last frost

• Start harvesting: Summer squash, cabbage

8 weeks after last frost

• Start harvesting: Acorn squash

9 weeks after last frost

• Start harvesting: Green beans, new potatoes, cucumbers, peas, herbs

Once you have figured out the planting date for each type of seed for your area, you can transfer those dates to your garden calendar. I use a Google calendar, but you could go paper, digital, whatever works for you. When that first reminder pops up, you can get out there and start planting!

But what if you struggle keeping your seed starts healthy? I can help! Check out Mission Healthy Plants for a quick 3-day course guaranteed to troubleshoot any issues and get your plants thriving.

How about if you need more help planning your garden? Check out my Garden Planning Masterclass for a done-with-you session where you walk away with the perfect garden plan for your family.