Search this Site

Starting Seeds Indoors
to Jump Start Spring

Page Contents

Vegetable Seedlings Happily Growing Under Lights

Starting Seeds Indoors

When you start to grow your own seedlings you will begin to realize all the different plant varieties you have been missing out on and a whole new world of gardening will open up to you.

There are many seeds that will germinate and grow well when sown, at the right time, directly to the main garden. Then there are those that will need to be started indoors giving you more effective control of the environmental factors that effect seed germination and seedling growth.

Below is a list of the vegetable seeds that can be started indoors and will later successfully transplant to the main garden.

Starting Seeds Indoors
ArugulaBroccoliBrussel Sprouts
MelonsMustard GreensNew Zealand Spinach
Squash SummerSquash WinterSwiss Chard

While potting mix, temperature, moisture, light, and timing are the five key points to successful seed raising it is important to regard it as a two stage process:

  • The first is seed germination.
  • The second is seedling growth.

The two stages need to treat separately because although most seeds germinate at similar temperatures their best growth afterwards depends on the type of vegetable they are.

If you are wondering where the first stages might end and the second stage begin the best point of reference is the point where the first true leave appear. At this point I consider the seed germination stage has finished and the growing vegetable seedlings stage has started.

Seed Germination

What seeds need for good germination and continuous growth.

  • Good Potting Mix
  • Temperature
  • Moisture
  • Light (or darkness)
  • Timing

Potting Mixture

A good potting mix for germinating seeds is a simple seed starting mix of either coconut coir fiber or sphagnum peat moss and perlite. Fertilizer is not needed for germination as there is a source of nutrients within the seed that will last until their root system and true leave are ready to take over. However if starting seeds in seed cells or any method where the seeds are going to grow from seed to finished seedling in the same container, seedling fertilizer is going to be needed from the beginning.


Soil temperature is very important for good seed germination. Most vegetable seeds will successfully germinate in temperatures between 60-75 F,(16-24 C). When starting seeds indoors in late winter early spring keeping the seed trays at a consistently warm temperatures during the germination process is probably the most important factor in successfully starting seeds.

If necessary, to keep the potting soil at the right germinating temperature, provide the bottom of the seed tray with heat. A heated propagating pad can be the most important item of your seed raising arsenal. Bottom heat helps to ensure your seedlings germinate uniformly and encourages strong root development by giving them an even and consistent heat distribution.

Propagating domes are another way to control temperature during the germination stage when starting seeds indoors.

Once your seeds have germinated and there is signs of life above ground remove any covering that will restrict seedling growth.


In order to germinate and thrive seeds need to be kept constantly moist, it is important not to allow the potting mixture to dry out or become excessively wet for too long a period. This is where a good free draining potting mix is worth it’s weight in gold. As with all stages of seed raising and seedling growth a good mixture should be moist, but not too wet, about the consistency of a wrung out sponge is good.


Although different seeds have varying needs for light during their initial germination most vegetable seeds don’t require light to germinate and will do so perfectly well without it.

However as soon as the young seedling appears above ground good light is absolutely essential so it is a good idea to have your seedling light source available and ready for when they do emerge.


One last very important thing, before you rip out and start throwing seed around, is timing. While gardening, and the correct time to starting sowing seeds is not an exact science there are several factors that will enable you to get it "right enough". Follow this link for a seed starting guide cheat sheet that makes working out the correct time for starting seeds indoors to ensure the seedlings are ready for transplanting when the time is right.

Sowing Your Seeds

Now that the basic conditions necessary for germinating seeds have been covered, it is time to get ready to sow them.

There is a huge variety of different pots and trays for starting seed and growing seedlings indoors, from commercial types to homemade and recycled containers. The best type of container to use will depend on several factors. Your experience, number of seeds needed, available time and what seed raising equipment you have are the main ones. Check out the “how to” slideshows below to help you decide which method is best for your situation.

related pages

After seeds have germinated, they need to be given the best possible growing conditions to insure stocky vigorous plants for outdoor planting. For the next page in this section follow this link to Growing vegetable seedlings

Share this page:
Enjoy this page? Please pay it forward. Here's how...

Would you prefer to share this page with others by linking to it?

  1. Click on the HTML link code below.
  2. Copy and paste it, adding a note of your own, into your blog, a Web page, forums, a blog comment, your Facebook account, or anywhere that someone would find this page valuable.

Home Page - Site Map - Top of Starting Seeds Indoors Page - Starting Seeds