Seed starting tips from our on-farm technicians
Too early to start seeds? Maybe, but not too early to start preparing to grow next year’s transplants. It seems to always be a rush in late winter to get all the supplies together for seed starting (especially for high tunnels and spring crops), and timing is everything when you are growing your own transplants. Some of you who are lucky might have heated greenhouses, but many of us will be starting plants under lights in our homes and basements – but it works! Shelving and shop-light systems can work well if you follow some simple rules:
- Keep the lights close to your plants – Do this to avoid leggy transplants. It is best if you can adjust the lights up or down with chains or a pully system to keep the lights just a few inches above your growing plants.Don’t let them dry out – Bottom-water systems can be helpful for this. I use heavy duty trays without drainage holes and add a few inches of water every 2-3 days, letting the trays fully dry out in between to avoid keeping the planting medium overly saturated.
- Use heat mats to warm the soil – Every type of plant has an optimum germination temperature, so make sure to pay attention to the seed packet. Peppers especially need some extra heat (75-85° F.) to germinate properly, so heat mats can make a big difference. Be sure to use a thermostat with a probe that sticks down into the planting medium to ensure it doesn’t overheat.
- Harden off your plants – Using a fan on a mild setting a few times per week while your plants are growing can ensure they are exposed to enough wind stress to be resilient in the field. Wait to do this until the plants are well established, and make sure they have plenty of moisture. As it gets closer to time to plant them out, you will want to introduce them to outdoor conditions incrementally so they can acclimate to more intense light and fluctuating temperatures.
To prepare for upcoming seed starting season, here are some things to make sure you have on hand:
- Planting flats and cell packs – try using heavy-duty reusable products (Winstrip is one company that makes them) to save money and reduce waste
- Seed-starting medium – the quality of your seed starting medium is important to success. Look for products that are specially made for seed-starting and avoid using other general purpose potting mixes that can be too course.
- Fertilizer suited for seedlings – You only need to feed maybe once a week. Use a mild/diluted fertilizer to avoid burning your seedlings. Liquid fertilizers (like fish emulsion) tend to be easier to apply and with nutrients more readily available to fast growing seedlings. You can also use a granulated fertilizer like Grow Appalachia’s Mountain Pride that has been soaking in warm water for a day or two as a fertilizer tea – make sure to dilute appropriately until it is the color of lightly brewed tea. Wait to add any fertilizer until after the seedlings have come up and are off to a healthy start.
- Seeds – If you don’t have your seeds ordered already, hopefully it won’t be too late to get the varieties you need for flavor, color, and disease/pest resistance.