GardenDesk: Indoor Seed Starting

Starting your own seeds has many benefits!

Raising one's own seedlings is invaluable to the organic gardener. It is great because it allows you to get started early, getting your hands in the dirt right about when Spring Fever hits. There are many benefits to starting your own seeds indoors, but my top three reasons are:

Potting Tomatoes with my Table-Top Gardener Portable Potting Tray
1. Organic From Start to Finish!
By starting the seeds yourself, you can be sure that your plants are raised organically - without chemicals. If you want to be 100% organic, look for seeds that were harvested from certified organic vegetables the year before. You can usually find a few organic selections from your favorite seed company. If that's not enough, look for companies specializing in organics, or with large sections of certified organic seed like Botanical Interests Online.

2. Your Seedlings are Well Taken Care Of.
When you buy seedlings from a garden center or hardware store, you don't know how those plants have been taken care of. Are they root-bound? Were they allowed to wilt in between watering? There are many things that can stress the plants that will affect their growth later on. When you tend seedlings in your own home, you can easily keep an eye on their needs.

3. You have an almost infinite amount of seed choices.
Garden Centers usually only carry a few varieties of each vegetable. When you buy your own seeds, you have many more choices. You can look for more interesting features or better flavor in your vegetable varieties. There are many more heirloom varieties available as seed than as plants. As an example, I raised 35 different tomato varieties last year and 28 of them were heirlooms.

What is needed to grow great seedlings indoors?

Through many years of starting my garden from seed in the house, I have encountered just about everything good and bad that can happen. Through trial and error, I have developed a system that works well for me and it really isn't complicated. So what do you need to start your own seeds inside?

1. A simple light system.

2. A good "soil-less" growing medium.

3. Warmth for seed germination.

4. Regular watering by bottom watering.

5. Care not to start too early.

Now let's go over these one at a time.

1. Give your plants plenty of light.

Lots of people have tried raising vegetables from seed in a "sunny window". Many times this doesn't work in the winter or early spring because it simply isn't enough light.

Plants need much more light than we do. A grow-light set up will work much better. There are many "grow lights" and special light spectrum bulbs available for purchase. These are great products, but I do not use them.

A simple table top light set like this one, or fluorescent 40-watt shop-light fixtures is all you need if you follow my three simple tips.

For many years I grew all of my seeds on an old table in the basement with light fixtures hanging from the ceiling.

When space was an issue, I hung a light above a small shelf in the laundry room:

With these set-ups, I took the lights down after the outdoor growing season was in full swing. Then, for a few years I dedicated one side of our basement to lights and kept them up all year long:

I built a double-decker table on one side from an old kitchen table and scrap wood.

This provides me with plenty of growing space... except when my extra-early tomatoes are just about ready to be moved outside. That's when it gets a bit crowded:

This year, I am moving the seed-starting table to the garage. I admit that my set-up has grown to be pretty large. I raise hundreds of plants with this system, but if you are new at this, you probably only need to find space for one or two lights.

I use standard cheap light fixtures with regular 40-watt fluorescent light bulbs and have found that there are three keys to making regular bulbs work as well as the expensive ones. The first tip is, you need to use new bulbs even if you have some old bulbs that are still working. Fluorescent bulbs get dimmer as they age. We don't notice this until they are about to burn out but the plants DO notice. We are substituting these bulbs for the sun, so they have to be as bright as possible!

The second tip is to keep the lights very close to the plants.

If you feel uncomfortable about how close the top leaves of your plants are to the lights, then you are doing well. I keep the lights as close to the plants as I can without touching them (actually it is even okay if some of the leaves do touch the bulbs from time to time).

This is why I like to hang the lights with chains. I move the light fixtures up a little at a time as the plants grow. I simply put toggle-bolt hooks in the ceiling above the lights to hang the chains on.

If you don't want to put hooks in the ceiling, you could build a wood frame to hang the light from our buy a light stand like the many Grow Light Stands available from Gardener's Supply Company.

The third tip about the lights is to leave them on for a long time each day but not continuously. 16 to 18 hours of light per day is not too much but they do need some amount of "night". I turn mine on when I wake up each morning and off when I go to bed. I do not recommend using an automatic timer to turn the lights on and off. I will explain why in the watering section below.

2. You need a good "soil-less" growing medium.

Do not use regular potting soil or outside garden soil to start your seeds inside. Potting soil is too heavy for young tender roots. It stays cold and either too wet or too dry. I always use new soil-less seed starting mix available from many different seed or garden supply companies. Not all soil-less mixes are called "Germinating Mixes" like the Germinating Mix pictured to the left. Many times you find it called Seed Starting mix.

You can make your own by mixing ingredients like peat moss, vermiculite and perlite, but I find it easier to use the pre-mixed kind to be sure its correct. A new mix that I would love to try is Gardens Alive's Natural Beginnings Seed-Starting Mix. All the ingredients are natural and the main one is coir, which is coconut fibers. I have great success with coir in my worm bin and in my upside down tomato planters. Coir is more renewable than peat moss and is said to retains more moisture and nutrients. Gardens Alive says Coir lasts up to four times as long as peat and can be reused several times for successive sowings. In addition to coir, Natural Beginnings contains worm castings and mealworm guano. Gardens Alive is always interesting like that! Those sound like great ingredients but you can get by with any mix as long as it is indeed soil-less.

3.Warmth for seed germination.

Most seeds need warmth to germinate. If you are only going to raise one or two flats of seedlings at a time, a great option is to use Seedling Heat Mats. Heat mats work really well because they provide constant and automatic heat to the flats of newly planted seeds. I usually start my seeds in the basement when it is still pretty cold, but I start 6 to 8 flats at a time and can't afford that many heat mat starters. I am usually able to keep the seeds warm by using trays with the clear plastic lids that form a mini-greenhouse. If I am out of that type of tray, I put plastic wrap over the pots. Then I put my trays in the laundry room where the clothes dryer and the furnace keeps them nice and toasty. The top of the refrigerator or on top of a heated fish tank would work as well. You can be creative but you must provide your newly planted seeds some sort of steady heat. Keep watching for the seedlings to sprout so you can move them to the lights as soon as they emerge.

4.Water only with "Bottom Watering".

I am convinced that this is where the most mistakes are made with growing seedlings. Your young seedlings need plenty of water. Constant light can dry out the soil quickly which stresses the plants. If you try to spray your plants from above, they probably don't get enough water. Also,the plants can get fungal disease if the leaves are allowed to stay wet and cold.

This is why I believe it is best to bottom water.

I use trays that hold water under my containers of soil and seed. All of my containers have holes in the bottoms to allow water in (or out). Peat pots work the best for this, or you can make pots with recycled newspapers. I also like to use the plastic cell packs that have holes in the bottoms.

I like to get my hands dirty, but If you don't, you can still have soil-less mix that is great for bottom watering by using Jiffy Peat Pellets and Dome Sprouting Trays that come compressed. Each Jiffy Pellet swells up when you add water and becomes it's own pot like this:

No matter what containers I am using, I place them in the water-tight trays. Then I fill the trays up about half way and the porous soil medium wicks up the water to feed the roots. I water almost every day by simply pouring water in each tray when needed.

This is why I don't use automatic timers to turn the lights on and off. If I have to manually control the lights, I get two built-in times per day that I am forced to check on my plants and give them water if needed.

5.Be careful not to plant too early.

This is usually the eager gardener's biggest mistake. Make sure you know when you plan to move the plants outdoors and the growth habit of each kind of plant you are raising. Research the recommended seed-to-transplant time for each vegetable or flower. For instance, tomatoes should only be under lights for 4 to 6 weeks before transplanting and you shouldn't transplant them outside until all danger of frost has passed. In my area, the average last frost is May 15th. That means that I should wait to sow main season tomatoes until mid-April. If you start too early, your plants will get spindly and root-bound. If you have to keep the plants inside longer than you planned, you may need to transplant them to larger pots which of course takes up more space.

Now, If you have never tried starting your own seeds indoors with florescent lights, I hope the length of this post doesn't make it look too complicated. I love managing the plants under lights. For me it is great fun. It is especially rewarding because I know that I can truly raise organic vegetables. controlling the plants' environment from start to finish. It is also fun because I get a chance to get my hands dirty when it is still too cold to dig in the outdoor garden.

I would recommend any gardener give indoor seed-starting a try!