Starting Seeds Indoors

After arguably the coldest, snowiest winter on record, I am ready for spring. Okay, maybe the winter of 1934 was colder. So what? I still have snow, and my woodpile is pathetic. I am picking up sticks and burning soggy remnants of previous woodpiles. To keep my spirits up on raw, gray days, I plant seeds indoors.


I started back in March, planting artichokes, onions, leeks and peppers. Now I am planting the brassicas: Brussels sprouts, broccoli and kale. Those hardy souls can go out around the time of the last frost, even if the ground is still cool. My tomatoes, the queens of the garden, I will start closer to mid-April and go in the garden in June – well after the last frost – when the soil warms up to 60 or more.


One key to success with plants indoors is having enough light. A bright, sunny windowsill might be enough for the first couple of weeks in a plant’s life, but to grow good healthy tomato plants for 8 weeks requires artificial lighting.


Shop lights are relatively inexpensive: a two-tube, four-foot fluorescent fixture should cost under $20, plus the bulbs to go in them – which vary widely in price. You don’t need fancy “Gro-Lights”. Those mimic the spectrum of daylight, but for starting lettuce and tomatoes for the garden, ordinary cheap tubes work just fine. And if you can mix cool white and warm white tubes, you can have something close to daylight wave lengths.

Homemade plant stand


A few years ago I built a simple wood A-frame plant stand that has worked out well for me. It uses 3 fixtures and will illuminate 6 flats of seedlings. I suggested at the time that your local lumber yard will be glad to take your parts list and cut lumber to the appropriate sizes. To get the directions, go to my website ( and type in “Plant Stand” in the search engine, and the article will come up. Or send me a self-addressed, stamped envelope and I will mail you the directions.


Another item that will help you is an electric heat mat to put under the flats while your seeds are getting ready to germinate. Most seeds have a protective mechanism to keep them from germinating too early. They need the soil to reach a certain temperature in order to know that winter has gone by. Garden centers sell 2 sizes: enough for one flat, or enough for four flats.


Last spring I started all my corn indoors in plug trays (containers with over 100 planting places per flat) and put them on a heat mat. They germinated in just 3 days – but would have taken 10 or more outdoors. Corn sometimes rots if the soil is cold and wet. Crows love to steal corn when it is first up, but I planted the seedlings when 3 inches tall and they rooted right in, so the crows didn’t steal a single one.


Moisture is another important factor when starting seeds indoors. Get your planting mix thoroughly moist before you plant. That can be done by placing a tray of planting soil in six-packs in a flat with water in it, and letting the water soak up from the bottom. Or pour water into the bag of soil mix the day before using it.


If the soil mix dries out when seeds are just starting to crack open and send out a rootlet, your seedlings will die. You can prevent that by covering the planted six packs with a plastic dome. These are clear plastic so you can see what is happening, and so that the seedlings that have germinated can get light while others are still waking up. By the time your seedlings are two inches tall, they will be crowding the dome and you should remove it.


Have you ever had bad germination rates? I have. It could be due to bad seed or old seed. In general it is best to buy new seeds every other year, even if you have plenty. Most seeds are good for 3 years or even longer – but at a lower germination rate.


But bad germination may also be due to the position of the moon and stars. I have been following a celestial calendar called “Stella Natura” ( for a few years now, and although I can’t prove that its advice is right, I’ve had some interesting results.


I planted lettuce seeds on a “leaf” day, and then some more the following day, which was a “blackout” day (not recommended for planting anything). Even though I used the same seed package and planting mixture, I got a very low germination rate for seeds planted on a blackout day, but the others did well. The calendar has good days for planting fruits, flowers, roots and leaves. But this year I followed the calendar and still got very low germination for my artichokes, so who knows?


Remember when you calculate the cost of your tomatoes that building a plant stand for $50 and then buying lights for $100 is a multi-year investment. If you like messing around with plants in spring, starting seedlings indoors is a good idea. You can get rare and unusual seeds from catalogs that you would never find at your local farm stand. And, as one of my fridge magnets says, Gardening is Cheaper Than Therapy!


Henry Homeyer is a fruit tree pruner and gardening consultant. Contact him at or P.O. Box 364, Cornish Flat, NH 03746.


Thinking of Spring, Starting a Few Seeds


          I’m not sick of winter yet. But I have to admit that recent warm, sunny days got me thinking about spring. I love to start seedlings in the house but recognize that it is still too early for most things. I have a couple of artichoke seedlings growing in a large pot, and will start some onions and peppers by mid-March.


The problem with starting seeds too early is that it is hard to meet the needs of your seedlings until the soil warms up enough to plant them outdoors. I have fluorescent lights and a nice plant stand. But as plants grow, they need bigger pots for their roots. As I start about 300 plants most years, I cannot give each of my babies its own 3- or 4-inch pot after they outgrow the six-packs many of them are started in. The solution? Start most things just six to eight weeks before they go outside – which for tomatoes and other frost sensitive plants is, for me, June 1oth even later.


Most commercial seed starting mixes are made of peat moss, perlite (a fluffy white substance that looks like Styrofoam), and some soluble chemical fertilizer. The assumption is that the mix will get plants off to a good start by providing a fluffy medium for young roots – but that you, the grower, will supply the “food” that your seedlings want after the first month.


After a month the chemical fertilizer will have either washed away or been used up. So what should an organic gardener do? There are fish or seaweed derived liquid fertilizers that you can dilute and add to the water you apply. They will supply the nitrogen, phosphorus and potassium found in a chemical fertilizer, and they will also supply calcium, magnesium, and many other chemical elements needed by your seedlings in small quantities.


Another solution, and one I favor, is to make a 50-50 mix of commercial potting mix with compost. My compost pile is frozen solid, but a good commercial compost such as Moo-Doo will do just fine – it will have healthy microorganisms in it. These bacteria and fungi help to process organic matter and turn it into chemicals that are easily absorbed and used by your seedlings.


Making Soil Blocks

Making Soil Blocks

Another technique is to make soil blocks using a small metal press that allows you to make 2-inch cubes of a packed soil mixture. This technique is more work, but provides high quality nutrition to your plants, and minimizes root shock when planted outdoors – seedlings grown in plastic six packs usually have tangled roots by the time they go outdoors, but plants started in soil blocks will not.



To make enough mix for about 300 blocs, mix the following ingredients in a wheelbarrow:

10 quarts of dry peat moss                                                                                              

1/4 cup limestone                                                                                            

1 cup azomite or granite dust (optional)


Then add and mix well:

10 quarts coarse sand,                                                                                       

10 quarts of peat humus,                                                                              

1/2 cup colloidal or rock phosphate                                                              

1/2 cup green sand                                                                                                       

1/2 cup organic blood meal


Finally add and mix well :

8 quarts of compost  (your own or purchased)                                                                                                

8 8 quarts of garden soil or purchased topsoil.


The mix is somewhat dry, and needs to be moistened and used in small batches. For a start, mix 4 quarts of mix with 1-2 quarts of water, stirring it with your hand (wearing a rubber glove). It should be gooey, but firm, not watery. Experiment with it until you find just the right consistency.


Soil Blocks

Soil Blocks

To make the blocs, make a pile of the gooey stuff 4-5 inches deep in a recycling bin or other flat-bottomed container. Then compress it by squishing it with the block maker, which makes four 2-inch cubes at a time. Fill up the cavities of the blocker, and then get rid of any excess by pushing the block maker down and rotating it against the bottom of the bin.


You can eject the blocks with the squeeze of the spring-equipped handle into in a standard black plastic flat, which will just hold 32 blocks. Line up the rows of blocs so that they do not touch. Block makers are available from Johnny’s Seeds and the Fedco Seed Company. And if you don’t want to make your own mix, some companies such as Grow Compost of Vermont are making a mix suitable for block makers.


Starting seeds is not for everyone, but I love it. It keeps me from getting squirrely as winter morphs into mud season while waiting for the snow and ice to disappear. Give it a try if you haven’t.


Henry teaches gardening and pruning to groups and individuals. His web site is