Skip to Content

When Is The Right Time To Start Vegetable Seeds Indoors?

It is the million dollar question every gardener wants to know as spring approaches : When is the best time to start my vegetable seeds indoors so they are ready for garden season?

Picking the right time can certainly be a challenge. Especially when you consider the consequences of starting seeds indoors too early or too late.

when to start vegetable seeds
Knowing the right to start your seeds indoors is vital to having strong, healthy plants when it comes time to plant outside.

Of the two, starting seeds too late creates the most serious issues. Plants that are small and weak will have a hard time adjusting to life outdoors. Not only are they more susceptible to damage from wind and storms, they can be easily damaged by pests too.

In addition, their small root structures struggle to survive in the large expanse of a garden. They can quickly dry out and wilt in dry conditions. Or, succumb to rot when the soil becomes saturated from a spring rain.

But unfortunately, starting seeds too early has its own pitfalls as well. Like having to transplant seedlings that have grown too large before it’s time to take them outdoors. And, finding space for the overgrown plants until it’s time for planting!

But here is the good news. Figuring out the right time is actually quite easy. It just comes down to knowing a few key facts about what you will be growing, and when it needs to be planted outdoors. From there, it’s just all about counting backwards!

How To Know When To Start Your Vegetable Seeds Indoors

Figuring out when to start your vegetable seeds indoors begins with knowing your area’s frost date. A frost date is the average date of the last light freeze that likely occurs in your area each spring.

small seedlings
If seedlings are too small when transplanting, they won’t be able to survive outdoors. It is important to start your seeds indoors early enough to allow for adequate growth.

It doesn’t mean you can plant exactly on that day without worry of a frost or even a freeze. However, it does give you a target for knowing you can plant a week or two after it with a fair amount of peace of mind.

Frost dates are published by a variety of on-line resources and are quite easy to find. In addition, most seed companies have them posted on-line too. Local extension offices are also a great resource for specific frost dates as well.

Counting Backwards From Your Frost Date / Planting Date

Once you know your last frost date and potential planting date, it’s time to see how long your seeds need to germinate and grow. And that information can be found right on the back of your seed packet.

tomato plants - frost
Planting too early can mean disaster for your plants, like this tomato plant that has been hit by an early season frost. Knowing your area’s last average frost date can prevent issues like this.

Most vegetable varieties will require an average of 6 weeks to grow to transplant size. Some will take longer, and others a bit shorter.

For instance, hot peppers can take 2 full weeks to germinate, so you may need to start them 8 to 10 weeks before planting day. Meanwhile, cucumbers and zucchini germinate and grow quickly, and may only need 4 to 5 weeks.

But once you know your frost free planting date, and how long your plants need for growth – all you do is count backwards to know when to start your seeds.

The Count Back Method

As an example, lets say you will be starting tomato seeds with a recommended time of 6 weeks on the seed packet. For this example, we will set June 1st as the target planting date.

Using the count back method, start by counting back 6 weeks, and then add one extra week for germination. That is a total of 7 weeks back from June 1st. In this example, it means you should start your seeds indoors on April 13th.

Knowing the approximate date you will be planting your garden is one of the big keys to knowing when to start seeds indoors. By counting back, you can find the exact date to plant your seeds inside.

It is a simple but totally effective method for always having your plants ready to go come planting time. It also allows plenty of time to get plants hardened off before planting day. See : Why You Need To Harden Off Seedlings – And How To Do It!

Growing Strong Seedlings – Start Your Seedlings Off Right

It is important when growing your own seedlings to make sure they have fertile soil to grow strong roots.

Always use a quality seed starting mix that is loose, drains well, and is full of nutrients. This certainly plays a huge role in plants reaching the proper growth level before transplanting.

One of the best ways to add power to your seedling soil is by mixing worm castings directly into the soil before planting seeds. Worm castings are an excellent slow-release fertilizer. And they are perfect for powering your seedlings to strong, steady growth in their first 6 to 8 weeks.

Here is to starting your seedlings at the perfect time this year, and to your best garden season ever!

This Is My Garden is a website dedicated to spreading the love and knowledge of gardening around the world. We publish two new garden articles each week. This article may contain affiliate links.