Starting Seeds

Why start your own seeds?  And when should I do it? Late March-early April is a great time to start many of our annual seeds. Many gardeners purchased their seeds in February and are just waiting for the growing season to get started. However, folks get antsy for spring in February and begin sowing seeds indoors.  I get lots of questions about how to manage seedlings that are long and stretchy.  Unfortunately, the answer to that question is to throw them out and start over at the right time. 

Starting your own seeds gives you the advantage of a bigger selection of more unusual varieties of flowers and vegetables. Garden centers and nurseries often carry the more popular and common varieties of flowers and vegetables in transplants, making it sometimes difficult to get unusual varieties.  Take advantage of seed catalogs for information as well as an opportunity to purchase unusual seeds. 

Be sure to look on the back of the seed packet for how long it takes the seeds to germinate. Seed catalogs often give this information as well. Count back from the time that you can plant seedlings outside. Allow for one to two weeks of growing time after germination and you’ll have your startup date.

For instance, I have a seed packet of red and yellow pear tomatoes. On the pack, it tells me that it takes 7-14 days for the seeds to germinate. In our area, you can safely plant out tomatoes by mid-May.  Counting back two weeks for the transplants to grow and another two weeks for the seeds to germinate, I’m looking at starting these seeds in mid-April. Giving a little time for mistakes or possible replant, the seeds should be started indoors by early April. 

After determining when the seeds should be started, giving the seeds the requirements they need becomes most important. Seeds need four things:  light, water, oxygen, and heat. Getting to know your seeds makes this an easy step. Again, reading the seed packet will tell you the depth to plant the seed.  Keeping the seeds evenly moist and the soil temperatures between 75°-85°F should provide just the right environment for these seeds to germinate – this is the heat and water requirements. The oxygen comes from the soil. Use a light, soilless mixture that is formulated for seed starting. All-purpose potting mixes can work as well, provided the seeds are not overwatered. All-purpose mixes sometimes hold more water. The soil will give your seeds and roots the oxygen that is needed for good germination and growth. 

There are a few seed starting setups that you can implement in your home.  One choice is to use a heat mat under the seed tray.  Heating cables work well too.  This provides the needed warmth for the soil. Above the seed tray, mount some fluorescent lights and lower them so they are just above the tray.  This will provide the needed light for germination. As the seedlings grow, the light will need to be raised.

Starting seeds in a brightly lit window is difficult. If this is the only option, be sure it’s in the south-facing window. Supplemental lighting is best, but not always an option. Also, be sure the room is warm. The cooler the room, the longer it will take for the seedlings to grow.

Before planting your seeds, find out if they need any scarification or stratification before planting. Scarification refers to breaking the seed coat.  This is sometimes needed for quicker germination of some seeds. For instance, morning glory and gourd seeds germinate quicker if you soften the seed coat by soaking overnight. Some seeds may require sandpaper to rough up the surface of the seed, or even a knife to nick the seed coat.

Stratification refers to the temperatures required for the seed to break dormancy and the seed to germinate. An example of this would be some types of acorns. It needs a cold period for the seed to break dormancy.  Also, many of our native plants will require a cold period for their seeds to germinate.

After the seeds begin to grow, they will send up what appears to be leaves.  This first set of "leaves" is called cotyledons. Next to develop are the true set of leaves.  The true leaves take on the identification features of the plant.  At this point, the seedling can be transplanted into a larger container or planted into the garden, if soil and air temperatures are adequate. 

Before putting the plant out, you may want to "harden-off" your plant. This means that the plant needs time to acclimate to the outdoors. This is done simply by setting the seedlings outside in a protected area for a few days to one week, then planting them in the ground. Be sure there is no danger of frost if you are keeping them outside overnight. You could bring them inside each evening if you are hardening off the plants during the time of possible frost damage.

Another way to start seeds is to do it now, outdoors. This is referred to as winter seed sowing.  January is the preferred month in our area to do this technique, but February works as well.

Winter sowing has to do with the stratification, as mentioned above, needed for some seeds. This technique typically uses milk jugs, orange juice containers, or water containers. These are almost cut in half, so that the top of the jug and bottom of the jug are "hinged".  Holes should be made in the bottom of the jug, allowing for drainage.

Soil is placed in the bottom (about 2"-3" deep). Seeds are then sown, as the packet recommends, and the "lid" is then closed and taped to the bottom part of the jug. The jugs are placed outside, which gives the seeds the needed cold period.  Allow the snow and rain to coat the jugs. Check the seeds for water throughout the rest of the winter, to avoid drying out.

This technique can be used for both perennials and annuals.  Cole crops do well with this treatment, as do native perennials. Annual flower seeds, especially the plants that do well in the colder temperatures, take to this process. With some trial and error, this will prove to be successful for many types of plants.

By: Mary Ann Ryan, Penn State Extension-Adams County

An upcoming series, The Vegetable Patch, begins Thursdays, February 22 – March 14, from 6:30PM – 8PM will give you a good basis for growing a vegetable garden, from starting seeds to harvesting, and everything in between.  We will talk about seed starting and give you an opportunity to start your own seeds in class.

To register, go to: https://extension.psu.edu/the-vegetable-patch . Space is limited. 

Whichever technique you choose, seed starting is fun; and you get to grow the plants that you want, not what the nurseries provide!  From vegetables to annuals to perennials, this allows you to learn a bit more about plants and how they grow.