Best Tips for Starting Seeds Indoors

Save money on vegetable seedlings and grow superior varieties of vegetables by starting seeds indoors.

| December 2012/January 2013

Starting Seeds Indoors

With a proper setup and some determination, you can start your own vegetable seedlings indoors.

Illustration By Elayne Sears

I began growing my own vegetable seedlings more than 30 years ago, and I still remember my sad first attempts. Many seedlings keeled over and died, and some seeds never germinated at all. Experience has taught me how to prevent these problems, and every year I deepen my garden’s diversity, save money and share favorite varieties with friends by starting seeds indoors. Thousands of superior crop varieties are rarely available as seedlings in garden centers, and the same goes for wonderful culinary crops, such as red celery and seed-sown shallots. If your gardening goal is to fill your table and pantry with an array of homegrown organic food, then starting plants from seed can help you achieve that goal. Starting seeds indoors under controlled conditions, with no aggravation from weeds or weather, allows you to get a prompt start on the season, whether you are sowing onions in late winter, squash in summer or lettuce in early fall. And where growing seasons are short, some crops require an indoor head start to later reach maturity.

The Germination Process

All seeds contain specialized cells that mobilize and grow when the germination process is triggered by moisture, temperature and sometimes light. Moisture and stored nutrients energize the embryo, which contains the latent structures for a plant’s root, stem and leaves. Most vegetable seeds that germinate quickly (such as cabbage and tomatoes) enter their dormant state with mature, fully formed embryos. The carrot family is at a disadvantage, however, because most Umbelliferae seeds (think parsley, fennel and dill) need time for their underdeveloped ovaries to grow before they can sprout. Other slow sprouters — spinach, for example — have compounds that inhibit germination in their seed coats. These compounds have to break down in the soil before the root and sprout can burst forth into the world.

Oxygen is vital to the germination process. Until seedlings have leaves to enable them to use solar energy, they rely on the food reserves in the seed combined with oxygen found in the soil to grow new cells. This is why you should always use a light-textured potting medium to start seeds, and why over-watering can cause seeds to rot instead of grow.

Appreciating the hard work that seeds must do during the germination process will likely enhance your seed-starting experience. You can watch time-lapse videos online of fast-growing bean seeds germinating, but watching them in person is even more amazing. The seeds that impress me most are squash. By the time the seedling leaves shed the seed coat, the little plant is already supported by a small mountain of roots.

Seed-Starting Mixtures

From the day they germinate, vegetable seedlings face challenges from fungi and bacteria in water, soil and air. The fewer troublemakers they face, the better they can grow, which is why using fresh seed-starting mix each winter is so crucial. Quality seed-starting mixes are formulated to discourage common soilborne pathogens that cause seedlings to rot, and to retain both water and air with ease.

You can make your own seed-starting mix by using either peat moss or coir as a base, and then blending it with compost that has been heated to 150 degrees Fahrenheit to kill any pathogens and weed seeds. Small amounts of vermicompost can be a beneficial addition when added to a seed-starting mix, but use no more than 10 percent by volume.

7/10/2016 11:30:51 AM

I saw an article years ago that described how to build the first Indoor Grow Light Plant Stand shown in this article. The article included dimensions, materials, etc. I'd gladly purchase a back copy if you have one available.

3/11/2016 6:29:33 PM

I love starting my own transplants. It is so much cheaper and I can grow plants that I cannot find at my local nursery. Oh, just to let you know, you can get a FREE copy of "Our Survival Essentials " during our FREE Promo days March 12th, 13th, & 14th 2016, So remember to grab your free copy during the next three days

3/4/2016 7:05:03 PM

Hi, i get worm casings from a friend who has worm beds. I want to use them as part of my seed starting mix and also as a liquid fertilizer. Can you tell me how much i should use per gallon of water and how much per pound of soil ?

2/19/2016 11:09:19 AM

I grew and flowered quite a few orchids under lights for many years. These were under simple 4 foot fluorescent "shop lights". I owned a hardware store for 30 years and could get all kinds of bulbs wholesale - I think I tried most of them, including some "plant lights" or "grow lights" that cost $12-15 EACH wholesale. In the end, I used simple "cool whites" for everything. The KEY is to have your plants (and here, seedlings) VERY CLOSE (within 2 inches) to the light bulbs. If your seedlings are close to the lights, you can successfully grow almost anything to a sturdy transplant-able size!

1/28/2016 4:42:42 PM

Great article! It's good to get advice from an experienced grower. My take on starting seedlings: Plastic water/soda bottles. They're everywhere & are free, plus you are cleaning up litter, making our environment look cleaner. Cut the top third of the bottle evenly all the way around. Turn it upside down into the bottom part of the bottle. Put in your soil, plant your seed, & water. Next time you water, just lift the top part & pour the water back into your soil & put the top third back on. Works great!

3/21/2015 2:57:18 PM

jenniferny -It will tell on the back of the seed package when to start the seeds before the last frost. It varies for the different type of veggies and even the different types within a species like tomatoes. I have some that say 6 to 8 weeks before last frost and others that are 4 to 6 weeks.

3/20/2015 11:39:00 AM

I would have thought that ANY article on seed starting would have included how long before planting the seeds should be started!!! Guess the author did not feel this was important enough to include!

7/21/2014 8:29:41 AM

One fun and easy plant to start from seeds is the TickleMe Plant. The TickleMe Plant will close its leaves and even lower its branches when you Tickle It!

5/19/2014 8:36:30 PM

Great article! I had always thought I was a "black thumb" when dealing with seeds, but I think my issues were using peat pots and not giving the seeds enough focused light. I started a batch in paper cups with organic soil mixed with vermiculite and VOILA! I have healthy seedlings that are bigger than my previous ones ever were ... and NO MOLDY PEAT POTS. The LED lights under my counter are perfect for 'incubating' seeds; I did not need special grow lights. Thank you for getting me to try gardening again after a few years of failure!

5/7/2014 2:08:48 PM

I started my seeds at the right time but I fear they did not have enough light and so their stems are weak and leggy. Most of them already have the third set of leaves. Can I put these in the ground after hardening them off or will they not survive because the stem can't support the growth?

3/29/2014 5:07:19 AM

I think you should be very careful while planting seeds indoors, you should chose the seeds which require less sunlight for indoor planting. And for some finest quality seeds you can visit

3/9/2014 10:11:16 PM

Hi, so just to make sure I understand you correctly, I should go out and buy new peat moss and vermiculite and not use my unused stuff from last year that has been sitting in my garage? Also, what do you think of the standard 6 cell black plastic seed starting tray with dome? Seems much more convenient than individual paper cups. Thanks! Super helpful albeit a bit overwhelming for the new gardener :)

4/30/2013 6:41:48 PM

This year I tried something that I usually don't do. I made my own pots from newspaper. I have to admit it was a little time consuming to do, but I think it will work great when I go to transplant the plants into the garden. This year I just did my tomatoes. I had my doubts abou the pots holding together but it seems to be working great! If anyone else is interested I found some information here: <a href=""</a>


barry norris
12/14/2012 7:51:40 PM

Thank you for an excellent article on seed starting. Do yo use straight vermiculite (fine grade?) to cover the seed once it has been planted into the mix?

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