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Seedling plants and the secret to a successful growing season

In the Garden

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Photos: Lance Ellis |

As many home gardeners try to be more self-sufficient and cut gardening costs, they look to starting their own plants at home. You can have great success with the right tools.

Start by selecting what plants you would like to grow in your garden or flower beds this coming spring based on how long your growing season is, and what kind of produce you want in the end.

After choosing the varieties of plants, determine how many weeks prior to transplanting they need to grow to reach an appropriate size before going into the garden. Generally, this information is found on the seed packet, but in case it isn’t, contact a county extension office for help. The indoor planting date will vary depending on seed type and when the last frost is in your area so they can be safely transplanted outside.

Starting your seeds too early can result in an overgrown plant with a bound up root system, (like if the pot is not large enough to handle the plant for an extended period of time). Planting too late can also be detrimental as the plant will not mature its fruit in time before the Fall frost comes. Selecting varieties of plants that will be able to mature their fruit in time are critical to having a successful garden.

Use a container that has sufficient room for root development for the size and time that the plant will be in the pot, as well as adequate drainage to prevent root rots and diseases from occurring. Most seeds you start will benefit from being planted in a seed starting mix that has a fine particle size, and adequate drainage characteristics for small seeds/plants. You can find seed starting mixes at local nurseries.

Seeds vary as far as their specific needs of sprouting and growing. A few seeds need light to germinate, and most others do not. Some seeds will need a warmer temperature to start to grow and others may need it slightly cooler. Smaller seeds most often can be sprinkled on top of the soil and lightly pressed into the growing media, while larger seeds many times will need some soil placed on top of them.

One of the difficulties of starting your seeds at home is the soil temperatures can fluctuate greatly. For example, a tray of seeds that are placed by a window can have temperatures vary during the day and night from 90 degrees at the hot part of the day, to 50 degrees or less that night. Many seeds germinate slowly or poorly under these conditions. To best control seedling germination temperature, buy a seedling heat mat. This allows you to thermostatically control the soil temperature from underneath the tray, and give the desired temperature for the specific crop you are growing. Using a plastic tray dome can help to reduce the temperature and moisture fluctuations of the soil, but they can also heat up and cause plants to heat stress and die. Placing a piece of newspaper on the top of the plastic dome during sunny portions of the day to provide some shade can mitigate this overheating action.

And of course, consistent moisture levels are necessary to avoid drying the seeds/seedlings out during germination and getting them started.

Prior to planting your seedlings outside, they need to be hardened off to prevent shock, and possible death. Hardening them off means getting them accustomed to direct sunlight, outside temperatures and other elements in a gradual process, rather than in a single day of planting. Many times putting them in a cold frame is the best method to get them accustomed to the outdoors. If you started your plants in a tray, then transplant them after their first true leaves have appeared. True leaves are the second set of leaves that grow after the first set of leaves appear on the seedlings. Be very gentle as you take the seedlings out of the soil and transplant them into a larger container so that you do not damage their fragile root systems.

Best of luck with your seedlings! For further seed starting tips please reach out to Lance at (208) 624-3102.