When it comes to planting your seeds, timing is everything. Besides cleaning and sharpening your garden tools, fixing your soil, adding amendments, and planning your garden, you'll need to keep a close eye on the planting season!

Starting your seeds may not sound like a difficult job; however, there’s plenty to consider before you start. So when should you start planting your seeds? Can all seeds be planted at the same time? Is there a difference between indoor seed planting and outdoor seed planting? Mulch more below!

Seed Planting - Where to Start

pepper seeds in hand

Image credits: Marco de Benedictis via Shutterstock

When you're eager to plant your garden, it can be tempting to sow your seeds as soon as the seed packets arrive at your doorstep! But before you open the packets, store them safely because timing is important when planting seeds indoors or outdoors because it's crucial to healthy plant growth.

If you plant them too early, your seedlings can become leggy or not grow at all; planting them too late will delay harvest. So, when's the right time to plant your seeds?

First, figure out your USDA plant hardiness zone to help you understand your area's climatic conditions. Then find out the average last spring frost date in your area. This will provide you with information on the number of weeks before and after the last frost date to sow your seeds indoors or outdoors.

The general rule is to plant cold-hardy crops like cabbage, cauliflower, and broccoli a couple of weeks before the last frost date and wait a week or two after the last frost date to plant warmth-loving plants like basil, melons, and peppers.

Remember, every plant is different, so do your research before planting. But does timing matter if you're starting seeds indoors? Yes, especially if you plan on transplanting them out in the garden when spring rolls by.

Lastly, ensure that the seedlings have six to eight true leaves before transplanting them outdoors in warmer weather.

Indoor vs. Outdoor Seed Sowing

If you want to gain a few weeks of growing time, starting seeds indoors is a great way to do it. When you start seeds indoors, you save time, so you can transplant seedlings instead of planting seeds when spring comes around.

However, you need the right setup to start seeds indoors. Besides investing in grow lights (if there's a lack of sunlight), you'll need dedicated space to house your seed pots or trays where they won't be disturbed.

You must monitor air, humidity, and moisture to prevent a mold attack. Just like outdoors, your plants need to be supplied with proper sunlight, watering schedules and fertilizing while inside. In short, starting seeds indoors is a commitment.

When it comes to outdoor sowing, you won't need to worry about transplanting or bound roots. While you'll still need to measure moisture and sunlight, your plants will already be acclimated to the unpredictable outdoors.

Indoor Seed Sowing

Hand placing lemon seed into pot

Image credits: verchmarco via Creative Commons

Sowing seeds indoors is pretty straightforward; however, the seedlings will require some extra love.

If you don't have access to sunlight, measure light before investing in grow lights to help your plants thrive. You will also want to avoid under- or overwatering your seeds. You can even create a mini indoor greenhouse to help them germinate.

Besides getting a head start, planting seeds indoors can help prevent pests and frost from damaging your seedlings, making indoor sowing a great option. It's also wonderful if you have limited or rare seeds because they're safe from foot traffic and cold weather.

There are many seeds you can sow indoors, but the most popular ones are:

  • Tenders - tomatoes, zucchini, chilies
  • Hardy annuals and veggies - sunflowers, broccoli
  • Tender herbs - basil
  • Annual climbing plants - morning glory, sweet peas
  • Perennials - echinacea, delphiniums
  • Half-hardy annuals - nasturtiums, cosmos

While you can sow them directly in your garden, wait until after the last frost date to prevent cold damage to your plants.

Outdoor Seed Sowing

sowing seeds

Image credit: redakter via Pixabay

Outdoor seed sowing is different from indoor seed sowing. Unless you're using raised garden beds, the seeds you sow directly on the ground outdoors aren't safe from foot traffic and weather conditions. Besides all that, you need to prepare the garden for spring planting before you can sow the seeds.

If you're growing them in raised beds, you can convert your raised bed into a cold frame to keep your seeds safe. You can even build DIY cold frames to help your in-ground seeds germinate and protect them from frost.

Cold frames are a fantastic alternative to a greenhouse, and you can customize them to fit tight spaces.

When Should You Start Planting Seeds

Child hands putting tomato seeds into fertile soil in germination tray
Image credits: llike via Shutterstock

Image credits: llike via Shutterstock

The answer varies depending on whether you plant your seeds outdoors or indoors. If you’ve chosen indoor seed sowing, here are some of the best plants to grow indoors and when to transplant them outdoors.

Crops

Starting (before the average last frost date)

Transplanting (relative to last frost date)

Basil

5 weeks before the average last frost date

1 week after the last frost date

Broccoli

6 to 8 weeks before the average last frost date

2 weeks before the last frost date

Cabbage

8 to 10 weeks before the average last frost date

4 weeks before the last frost date

Cauliflower

6 to 8 weeks before the average last frost date

2 weeks before the last frost date

Cucumber

2 to 3 weeks before the average last frost date

1 to 2 weeks after the last frost date

Eggplant

6 to 8 weeks before the average last frost date

2 to 3 weeks after the last frost date

Melon

1 to 2 weeks before the average last frost date

2 weeks after the last frost date

Onion

10 to 12 weeks before the average last frost date

4 weeks before the last frost date

Pepper

6 weeks before the average last frost date

2 weeks after the last frost date

Pumpkin

1 to 2 weeks before the average last frost date

1 to 2 weeks after the last frost date

Squash

1 to 2 weeks before the average last frost date

2 weeks after the last frost date

Tomato

6 to 8 weeks before the average last frost date

1 week after the last frost date

If indoor seed sowing doesn’t work out for you and you want to plant your seeds in the garden, here's what you need to know:

Crops

When to Plant the Seeds

Beans

On the day of the last frost

Basil

1 week after the last frost

Carrots

2 to 3 weeks before the approximate day of the last frost

Corn

From the last frost date up to a week after

Cucumber

1 to 2 weeks after the last frost

Lettuce

3 to 4 weeks before the approximate day of the last frost

Peas

6 weeks before the approximate day of the last frost

Pumpkin

2 weeks after the last frost

Spinach

4 to 6 weeks before the approximate day of the last frost

Squash

2 weeks after the last frost

You're Seed-Sational!

When it comes to planting seeds, there are two ways to go about it. You can start them indoors ahead of time or wait until it's appropriate to sow them outdoors. Pick the method which works for you, but ensure you get the timing right.

This is because if you plant them too early, you risk stunted growth, and if you plant them too late in the season, your plants won't have enough time to establish themselves. If you've bought your seeds online, read the packet to understand the plant's recommended planting time to ace the seed germination game!

Leave your experiences, thoughts, and questions in the comment section! And share with friends and family who might find this helpful.