How (and When) to Start Seeds Indoors

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Are you wondering when to plant seeds indoors so you can get a head start on your garden? Here’s a hint – don’t plant all your seeds at once. Each vegetable variety grows at a different rate and has a different suggested planting time based on the date you transplant it to the garden.

This article shares tips for when to start seeds indoors and provides a link to a seed starting schedule you can print out for home use!

Starting Seeds Indoors

In general, seed packets will tell you to start seeds a certain number of weeks in advance. The number of weeks is determined partly by how fast the seed will germinate and grow and partly by how big the seedling needs to be before transplanting.

Your earliest batch of seeds might include onions, eggplant, and tomatoes, whereas veggies like cucumbers and winter squash pop up so quickly they need less time inside to get established.

If you start a vegetable too early, it could get “leggy, ” meaning the stem grows very tall toward the light and gets too skinny. You’ll also outgrow the space you’ve allotted with huge veggies if you start too early, and your veggies may bust out of their pots.

Here are some basic guidelines for when specific varieties should be planted:

• 10 weeks before the last frost: Eggplant, Celery, Onions, Scallions, Leeks
• 8 weeks before the last frost: Peppers, Tomatoes, Tomatillos
• 6 weeks before the last frost: Herbs
• 5 weeks before the last frost: Broccoli, Brussels Sprouts, Cabbage, Cauliflower, Cucumbers
• 4 weeks before the last frost: Lettuce, Melons, Squash

How to Organize Seed Starting Schedule

We have two strategies for organizing our seed starting schedule.

First, we store our seeds in sealed plastic baggies grouped by planting date. For example, we keep tomatoes and peppers in a bag labeled “6-8 Weeks Indoors.” This keeps us from forgetting anything and helps us keep track of what we want to plant and which seeds need replenishing for the next year.

Second, we post a seed-starting schedule in our seed-starting room with dates filled in. Scroll down for a link to our fillable seed-starting schedule!

Tips for Creating a Seed Starting Schedule

The recipe for creating a seed starting plan is pretty simple:

Step 1: Choose the Varieties You Want to Plant Inside

Not all vegetables can or should be grown indoors. Many will do much better when planted directly in your garden. Typical indoor veggies to start include tomatoes, onions, eggplant, summer and winter squash, melons, and greens.

In addition, buying a packet of seeds may not make sense if you only want one plant of a certain vegetable. To learn more about which veggies should be grown indoors and which veggies make sense for you, check out our article on choosing seeds to grow indoors.

Planning out how many of each vegetable you want to plant is helpful. We tend to plant about 20% extra for any failure to germinate or transplant. This will help you to determine how much space you need and what you’ll need for supplies.

If you are looking for high-quality seeds, we highly recommend both High Mowing Organic Seeds and Renees Garden Seed Company. We have been using these seed providers for a long time and almost always have positive results with their products.

Step 2: Determine the Average Date of the Last Frost

You can find your average date of last frost on the Farmer’s Almanac website. This date tells you when it will be safe to begin preparing seedlings to transplant into the garden. You’ll use this as the date you backtrack as you determine when each seed should be planted.

Step 3: Fill in a Seed Starting Schedule with Planting Dates

Using the average date of last frost, plus typical planting dates for most veggies, you’ll now plan out your seed starting schedule. Read the seed packet for specific varieties to confirm that the typical dates provided on any seed starting schedule apply to that particular type.

To simplify the seed-starting process, we’ve created a downloadable seed starting chart available in our shop. Simply fill in your average date of last frost, then use the suggested timetables to determine when you’ll start each group of seeds.

As a bonus, this packet also includes a planning sheet to help you track what you planted, when, and how many seedlings succeeded.

Step 4: Divide and Store Seed Packets

Once you know when each seed will be planted, divide your seed packets into categories or put them in order in your storage bin so that each batch is ready to go.

Step 5: Set Up Seed Starting Operation

You’ll need to lay a seed-starting center of operations based on the number of vegetables you want to plant. You’ll also need a light source, soil, potting supplies, a fan, and a watering can.

Your location will also need to be fairly warm. If your basement furnace runs fairly consistently, you can use a grow light near it; another option is installing heat mats or a space heater in a section of your garage. If neither of those is an option, create a smaller seed-starting operation in the living area of your home, but keep the number of veggies you plant in check!

STEP 5: Plant according to your schedule

Now that you’ve planned out your seed-starting schedule, follow it! Use our tips for planting seeds and caring for them to ensure good results.

More Seed Starting Resources

Planting seeds can be a great, cost-efficient way to support a big vegetable garden, and we’ve provided all the resources you need to make it happen!

• Seed Starting Supplies
• Seed Starting Supply Shopping List on Amazon
• Choosing Which Veggies to Start Inside
• Planting & Caring for Seedlings
• Preparing Seedlings to Transplant