Gardeners often spend the snowy days of winter planning spring planting. Starting seeds indoors is a great way to get a jump on the growing season, and watching tiny seedlings emerge on a windowsill is a wonderful reminder of spring during late winter snowstorms.
Here’s what you need to get started:
- A plan. Make sure you know your space. As soon as you start shopping for seeds, you'll want everything. Check mature sizes and plan accordingly. Be honest about how much time you're willing to spend in the garden. Beginners might want to stick with a small selection of their favorite fruits and veggies.
- Seeds. Stop in and browse our curated selection of seeds, we stock flavorful heirloom favorites and disease-resistant hybrids. Check out staff favorites like Cosmic Purple Carrots, Rainbow Blend Beets, and Rainbow Quinoa.
- Potting soil. Choose something light and fluffy to nurse the tiny roots along. A mixture of soil, peat, and perlite is best. We like Fertilome Seed & Cutting Mix.
- Containers. Large-scale gardens may require full size flats, but first timers may want to stick with biodegradable peat pots to start off their gardening experience. These pots get planted directly into the soil, reducing the chance of root damage during transplanting. Pick up a plastic tray to hold them and help with watering.
- Light. Most homes will need some sort of supplemental light for seedlings to grow properly. Pick an option that works for your space. There's inexpensive bulbs that will screw into any fixture, full-scale grow light systems with racks and heat mats, and everything in between.
- Heat source. Seed starting mats warm the soil from below, decreasing germination time. For beginners, the top of a refrigerator is a good spot to warm the seeds.
- Plant labels. Label your seeds right away. Whether you turn it into an art project or stick with utilitarian labels, make sure you know which seeds are which.
- A notebook. Keep track of your successes and failures. It's helpful to refer back to when seeds were planted, when you noticed them poking up out of the soil, and when they were transplanted. Gardening is always an experiment. Failures offer opportunities for growth as a gardener, so be open to the lessons!
Planting seeds too early or too late can complicate the process. Beginners should stick close to these dates. Seedlings planted too early can outgrow their pots before the weather warms, those planted too late won't be ready to transplant and will miss valuable growing time outside.
Early March: Brassicas like broccoli, cauliflower, and cabbage
Mid March: Peppers and eggplants
Late March: Tomatoes
Early April: Melons, squash, and cucumbers, though these can also be sown directly into the ground later in the spring.
Step by step
Read the directions on the seed packets. Check the for directions on seed prep, some will need to be scored, chilled, or soaked. The packet will also give instructions on when to plant inside or direct sow outside, based on the last frost. Our average last frost date is May 9.
Fill your containers with soil, leaving a half inch of space at the top of the container. Tamp down the soil, water until it's uniformly moist, then let it drain. Press the seeds into the containers. Fine seeds generally sit on top of the soil, larger seeds can be covered with soil. Seed depth should be one to two times the width of the seed. Gently water the seed. The best way to water is to soak the containers, allowing the soil to wick up the water from below. When the soil is moist, remove the containers from water and allow them to drain. Don't forget to label your plants!
The seed packet will tell you the average time it takes for the seeds to germinate. During this time, the seeds need to be warm and uniformly moist, but not wet. Cover the containers with plastic wrap or a plastic tray cover to create a humid environment, and set them on a heating mat or the top of your refrigerator. Check them every few days for signs of life.
When the seedlings start to emerge, move them to a location with lots of light and slightly cooler temperatures. This will encourage sturdy growth. Seeds will need about 12 hours of good light each day to prevent them from getting leggy. It's easiest to plug a grow light into a timer and set it appropriately. Grow lights need to start out within a few inches of the seedlings, and should be adjusted as the plants grow.
Continue keeping the seedlings evenly moist, and fertilize weekly. When using an all-purpose fertilizer, mix it at one quarter strength so seedlings don't burn from the nitrogen. Organic fertilizers are usually low strength and work well for young seedlings. If seeds were planted close together, thin them out as they grow until only a few strong seedlings remain.
Seedlings will need to be hardened off before they're transplanted outside. Two weeks before transplanting, start to back off on water and fertilizer. A week before transplanting, set the seedlings outside in dappled sunlight for a few hours each day so they grow accustomed to natural light. Slowly increase the amount of time they spend in the sun. Continue to protect the seedlings from cold temperatures.