Starting Vegetable Plants Indoors from Seed

How to Start Your Vegetable Plants Indoors

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Supplies you will need:

-     Seed.  Make sure you start with a good-quality seed.  If you have a favorite tomato and saved the seeds from that, they would be perfect. Fresher seeds have a better germination rate than seeds lying around in a cupboard for years.

High-quality seed starting or soilless mix: This mix is formulated to have great drainage and water-holding capability and minimize the onset of disease or soil-borne fungus.  There is no soil in this mix at all.  It contains mostly peat moss, pearlite, vermiculite, minor nutrients, and wetting agents. 

Either of these potting mixes work very well. I have used both. Click on the image to see the details.

Containers   Use containers that have drainage holes.  Old pots from previous years work great, and egg cartons that you pop a drainage hole into the bottom of each holder also work great.  If you want to purchase a seedling starter kit, this one below includes lights and vents, so it is a great start. Lights are required once the seeds have germinated unless you have a great window to use. If the plants do not receive enough light once up, they will stretch and become weak and leggy. Click on the image to see the details about it.

Grow Lights and Heat Mats:  You will need light once your seedlings have started growing their first true sets of leaves.  A heat mat is also a great idea, although not mandatory. It heats the soil without making it too warm, and it keeps the soil at a consistent temperature for faster germination. I have used the heat mats shown below and they worked very well.  If you have an amazing window, that will work great for light.  These heat mats work very well if you want to warm your soil and keep it at a

Fertilizer:  Once the plants have reached the stage of the first true sets of leaves, you will need a fertilizer to add nutrients to the soil. If you use soil with fertilizer added, such as the examples above, you will not need any additional fertilizer for your seedling starts. Liquid fertilizer is easiest to use with seedlings. Just add to the water when you are going to water your seedlings. Follow directions on the packing for use.

This is a great fertilizer using plankton if you are looking for an organic fertilizer. Click on the image for details

This is a great fertilizer for all around use for all season. It is not organic. Click on the image for details.

Steps:

Step 1: Take your soilless mix or seed starting mix and add some water to it.  This will activate the wetting agents, so the soil does not dry out too easily.  Mix it with your hands like you were trying to mix butter into the flour.  When finished, your soil should make a loose ball - not stick together totally, and no water should drip out.  

Step 2: Fill your containers with the soilless mix.  Be sure that there are drainage holes in your containers. Do not pack the soil; loosely fill it.  You can tap the container to ensure no air holes but do not pack.  

Step 3:  Knowing how many of these plants you will want to grow for your garden, plant a few extra seeds of each variety if the seed does not germinate.  The back of your seed package will instruct how deep to put the seed.  As a general rule, it should be 2-3 times deeper than the width of your seed.  If the seeds are tiny, they can just lay on the soil.  Do not cover them.  They will need some light to germinate.  If you are worried about them drying out, add a thin layer of vermiculite to the top, but it is unnecessary. Label each container as you go.  

Step 4:  Once all the seeds are planted and labeled, they must be put in a warm place.  This is where the heat mats come in handy.  Seeds germinate much quicker and easier with bottom heat.  If you are planting peppers, for instance, they are harder to grow, and bottom heat will greatly increase your chances of germinating them. 

Some extra tips on germinating:

For extra hard seed casings, you can use a file for sanding the outer coating, so the seed takes moisture easier.  Another method would be to take a small nip out of the pointed end of the seed with a toenail clipper (similar to cutting your nails). That works great for seeds like oranges, lemons, and citrus.  One final method worth noting is using a wet paper towel on a plate.  Place the paper towel on a plate and make it very damp.  Place your seeds on the paper towel and cover them with another layer of damp paper towel.  Make sure it is wet enough that it doesn’t dry out.  Keep checking it for moisture.  When the seeds have sprouted, you can plant them in your containers.  

Step 5:  As soon as the seedlings emerge from the soil, the pots must be put in a bright location.  A great sunny window or a supplemental light source will yield good results.  If using grow lights, they should be 3-4 inches above the plants.  You want to remove the heat mats now, and the sunny window should not be hot.  If the seedlings are too warm, you will get long spindly plants.  Keep them cool, about 65 to 75 degrees Fahrenheit.  This is important.

Step 6:  Once your plants have their first true sets of leaves. (The first leaves you see are the cotyledons).  The first true sets of leaves come after these.  Use a weak fertilizer solution at the start until your plant has two or three sets of leaves. If your soil is enriched with fertilizer, you do not need to add additional fertilizer at this time. Once they have three sets of leaves, start with additional fertilizer.  If you have too many plants in your containers, thin them out but cut out the plants you do not need. Let the best plants take over the pot.  To keep them all, you must transplant them by removing them from the pot and gently separating them. Then put them into a container on their own.  Water them in and let them continue to grow.

Step 7:  Once the weather outside is warming up, you should have healthy, strong plants.  Before planting them outdoors, you must harden them off (get them used to the outside temperature, sun, rain, and humidity levels).  Do this by moving them outside during the day, increasing the time they are out there for the next 7 to 14 days.  Start with indirect light, so they do not burn from the sun.  They must be brought back indoors in the evenings or near the end of the two weeks; if it is too cool, you can cover them to protect them from the cold.  You do not want it to get below 50 degrees Fahrenheit.  

Step 8:  Once they can stay outside and thrive in the conditions, they can transplant into the garden beds or containers. 

For more information on Vegetable Gardening, get our free copy of A Complete Guide To Vegetable Gardening For Beginners.