An easy way to check for seed viability is through a seed viability test. There are several tests you can do to see if the seeds are viable. I prefer the wet paper towel test. Let’s face it, I utilize this test because it’s the easiest! If the seeds are viable, you can get an estimate on the percentage of viability for the entire pack of seeds. 

Just follow these steps…

• Take a paper towel and completely wet it. 
• Place 10 seeds of your choice on ¼ th of the wet paper towel
• Fold the paper towel over the seeds so they are completely covered
• Fold the paper towel again so it is now 1/4th of the original size and can fit in a sandwich or quart sized bag
• Label a sealable sandwich or quart sized bag with the name of the seed and the date
• Place the paper towel with the seeds in the sealable bag 
• Make sure the bag is completely closed and sealed
• Leave the bag in an area where it will not be forgotten 

The original seed packet will say approximately how many days the seeds take to germinate. After the required amount of days, it is time to check the seeds.

• Open the bag
• Carefully remove the paper towel
• Gently unwrap the paper towel
• Count the number of seeds that have germinated
• Multiply the number of germinated seeds by 10
• You now have an estimate of the viability percentage

If you have nine seeds that have germinated, you can safely assume you have 90 percent viable seeds. In that case, you can plant as directed on the package. If you have 5 seeds that have germinated, the germination rate is 50%. You will need to sow two times as many seeds to get the same number of seedlings . Therefore, if the package recommends 1-2 seeds per cell, you should sow seeds at the rate of 3-4 seeds per cell to increase the likelihood of germination. 

You can plant the germinated seeds as usual, being careful not to break the roots from the sprout. If there was no or a poor germination rate, you can discard the seeds before you have invested any time in planting them in your garden

General Care-

Once the seedlings have germinated (typically 80% of plants at least), I remove the lid, remove them from the heat pad, and place them under lights. If they are just starting to erupt, I spray the soil to dampen it. Typically, I will start bottom watering only unless there are individual cells that are drier than others. Moisture levels need to be checked once per day at a minimum. It doesn’t take long for fragile seedlings to decline if they are not monitored for adequate water, light, or temperature. I also monitor for fungus gnats with sticky traps. 

Lighting- 

Once your seeds have germinated, it is important to supply adequate light. A sunny windowsill is not a sufficient amount of light. It is not strong enough and there are not enough hours of natural light to supply the amount of light needed for seedlings. I use simple LED 4-6 ft long shop lights positioned approximately 2 inches from the plants. I set them on adjustable chains so as the plants grow I can adjust the light distance from the seedlings. I set the lights on timers to supply about 16 hrs of light per 24 hr. period. 

Water-

Typically, the water present in the water and seed starting mix used when sowing seeds is enough for seeds that germinate in 7-10 days. This is why thoroughly mixing water with the seed starting mix before packing the tray is so important. The soil will start to dry in most cases in 7-10 days and require remoistening. For the seed trays that contain seeds that have not germinated after a week or so, I spray water with a spray bottle to keep the soil moist. I spray both the soil and the lid and then I reapply the lid and place it back on the heat mat. I utilize this method so I do not displace seeds by top watering. I also do not want to over saturate the soil at this point. Once the seedlings have germinated (typically 80% of the cells at least), I remove the lid, remove from heat, put under lights, and start bottom watering. I fill the bottom solid tray with about ¼ inch of water and place the cell tray back into the solid tray of water. As shown in the photo below, the roots will absorb the water and the soil will become saturated from the bottom up. Foliage does not need water. The roots are where the water is needed.

Temperature- 

When growing cool season annuals, I keep the room at approximately 55- 60 degrees Fahrenheit. That is the temperature of my basement grow room unheated in the months of January, February, and March. I modify this temperature as needed by opening and closing the grow room door. I also keep an inexpensive indoor room thermometer in both the grow room and my main basement area to monitor the temperature and open a heat vent if needed. You could also use a space heater intermittently if needed.

When growing warm season annuals, I keep the room at approximately 70-75 degrees. That temperature is easily achieved by opening a heat vent and keeping the door closed in my grow room. Again, I monitor the temperature with indoor room thermometers.  These thermometers also monitor the humidity level. 

Final Words-

Successfully getting seeds to germinate is exciting! When you see those little babies popping out of the soil it immediately feels like a success. One day when you come to check on your seedlings you will see the seed erupting from the soil and the next day you will see it has fully emerged. In this picture on the right, the seed is still attached to the stem before the first leaves have developed. Make sure to ensure continued success with adequate water, light, and temperature monitoring. Pretty soon these little guys will be ready to plant outside!!! 

Containers, seed starting mix, and labels

Make sure to have all your supplies ready. To see the supplies I use, refer to the https://www.shawnlvieth.com/seedstart1/ blog. or you may refer to the links at the end of the post.

Step 1. Set your containers and other supplies on a flat surface.

Step 2. Moisten your seed starting mix with warm water.

Step 3. Add water to mix until saturated, but not so wet that the soil drips water when squeezed.

Step 4. Fill in the seed tray with moistened starting mix, tamp the tray against the table to help settle the soil, and add soil until the tray is full. Do not compress the mix.

Step 5. Label the seeds you will sow and add the date of sowing. Don’t wait until later. It is likely you will forget which seeds you sowed. Save the seed packets for reference.

Step 6. I put the labels in before sowing the seed, because I know exactly how many of each seed will be in each tray. Alternatively, you can add the labels as you sow the seeds if you are putting multiple varieties in one tray. Make sure to only put seeds with similar germination requirements and timing in the same tray.

Step 7. Seed can range from large …..

Step 8. To very small

Step 9. I often use the envelope the seeds come in to sow very small seeds. If they are larger, I will pour them in my hand and drop them in each cell. I typically add two seeds to each cell to ensure as close to 100% germination per cell as possible. Seed that is not fresh (more than one year old) will have lower germination rates so additional seeds per cell may be beneficial. 

Step 10. A toothpick may be useful for separating and planting very small seeds.

Step 11. Larger seeds are much easier to see, but small dark seeds are almost invisible once they hit the soil.

Step 12. Tamp down the seeds, as needed, to make sure they are making contact with the soil. I often use the end of a Sharpie marker. Another object may be used, just be sure the seeds are not likely to stick to it when touched. 

Vermiculite, bottom trays, and clear dome lids

Step 13. Put the cell tray into a bottom tray without holes. This allows for watering from the bottom when needed as well as support for the seed trays.

Step 14. Cover the seeds with a fine dusting of vermiculite. You can also use a light layer of soil, but I prefer using vermiculite. It covers the seed and inhibits fungus growth on top of the mix.

Step 15. Cover the seed tray with a clear dome lid to maintain moisture.

Step 16. I am adding a soil probe for the thermostat that controls the temperature setting of my professional heat mat. I have the temperature set to 70 degrees. If you have a conventional heat mat, the temperature automatically adjusts to 10-15 degrees above the ambient temperature of the room the setup is in.

Step 17. Here is my seed set up on my 5 ft long heat mats. These heat mats are daisy chained to each other. You do not need to have your light source on yet. It will not aid in germination. The black cover on the left hand side of the rack is a flat with Larkspur. It has a black cover to provide darkness. This seed germinates in cooler conditions and darkness. Therefore, it is not on the heat mat and does not have a clear cover. Be sure to read the seed package to see the best ways to sow particular seeds. 

Note: I would not recommend Bupleurum, Poppies, Lisianthus, Bells of Ireland, or Larkspur for your first indoor seed sowing experience. They demand special conditions to germinate that are more difficult to achieve indoors. Great easy germinators indoors are Zinnia, Cosmos, Strawflower, Sunflower, and Snapdragons. Yarrow is the easiest perennial I have grown from seed. It typically will flower in the first season which is not common for perennials grown from seed. 

Here are a few of the products I prefer when seed starting…

Bootstrap Farmer 72 Cell Seed Starter Tray–

Very durable for reuse each year

https://amzn.to/42AcSBY

Bootstrap Farmer 1020 Trays (bottom trays, no holes) 

Very durable for reuse each year, I have yet to crack or break one

https://amzn.to/3weTTAR

Johnny’s Selected Seeds Madame Butterfly Bronze Snapdragons

Consistent and reliable seed source

https://amzn.to/3HTVcYo

Burpee Fine Grade Horticultural Vermiculite

https://amzn.to/3STmFzA

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