Indoor seeding gives you a jumpstart on the growing season and gives your plants a better chance of survival. Last year, we discussed how to grow plants from seeds, including indoor seeding versus sowing, in one of our blog posts. This year, we decided to dive into some more detail by sharing some of our favorite techniques for successful seeding, germinating, and transplanting. If you're planning on starting your annual flowers or garden edibles from seeds this year, you'll want to take a look!
Seed Starting Tips
Starting seeds indoors is a beneficial but sometimes intimidating task. Think about it-when you bring a new, already-established plant home, all you have to do is keep it alive. However, when you're starting from seed, you're responsible for nurturing it from a tiny seed into a mature plant. Don't let that intimidate you too much; successful seeding is pretty easy with our tips and tricks! Read the package:
It might seem obvious, but we can't skip over the fact that the best instructions for starting your plant are written right on the packet! Each plant will have specific requirements and guidelines for planting. Check the package for planting instructions, including depth, spacing, light, and moisture recommendations. The package should also indicate how much time your seeds should take to germinate, which you can use to figure out the proper timing. Count back from our last expected frost date for the year, which is usually around the last week of May in the Bismarck area. Choose the right containers:
You can use almost any kind of container for starting, but we recommend using a multi-celled planting tray to keep your little starters safe, cozy, and conveniently organized. By planting in single cells, it'll be much easier to remove and transplant the ones that germinate successfully and grow into little seedlings. Regardless of the container, make sure it's at least 2-3" deep and equipped with proper drainage holes. File tough seeds for easier germination:
Plants that grow from hard-coated seeds, such as nasturtiums, morning glories, sweet peas, and spinach, tend to be harder to start. Their tough outer-coating is harder to break down, making germination difficult for these plants. To speed up the process and increase your chances of success, you can help break down this hard coating yourself before planting. Gently rub the surface with a piece of sandpaper or a metal file-just be careful to stop once you see the soft, inner part.Use fresh, sterile, moist potting mix:
Never use dirt from the garden for container-grown plants, especially not your vulnerable little seeds! Always use a fresh, sterile bag of potting mix to ensure your plants grow in a rich, disease-free, and pest-free environment. Make sure to moisten the potting soil before planting, and pack it firmly in the container. Use seedling heat mats:
Many plants require warm temperatures to germinate. Since prime indoor seeding time happens during the spring, when Bismarck is still covered in snow, it can be hard to avoid cool drafts inside our homes. Keep your plant babies warm and cozy by placing your trays on seedling heat mats. Heat mats should be plugged into a thermostat controller to prevent them from getting too hot on warm days-you wouldn't want to roast your plants! Use grow lamps:
Although they often require darkness at first, seedlings usually need light to grow once they begin to poke through the soil surface. While a sunny, south-facing window is sometimes bright enough, limited space or cloudy days can lead to weak and leggy seedlings. Grow much stronger, healthier plants by using a grow lamp. Although they may seem pricey at first, the reduction in seed and soil waste makes them a sound investment. Plus, you can grow your plants anywhere in the house-no more cluttering up the kitchen table for weeks at a time!
When and How to Transplant Seedlings
Timing is critical when starting seeds indoors. You want your seedlings' readiness for transplanting to coincide with the last frost date so that you can safely transplant them outside. You'll know your seedlings are ready to transplant when they have 2-3 sets of leaves, and there's no risk of frost in the forecast.
After spending a few months in a warm, sheltered environment, transplanting your still-fragile seedlings outside can cause them a lot of stress. All seedlings should go through the process of "hardening off" before being permanently planted outside. Hardening off involves introducing your plants to the great outdoors gradually over time.
On a nice day, about 7-10 days before you plan on transplanting them, place your seedlings in a shady spot in your backyard, then bring them back inside. Repeat this cycle for three days, increasing their time outside by about an hour or two each day. On the fourth day, you can introduce them to dappled sunlight, rather than shade, for a few hours. Repeat this for a few days until finally leaving them outdoors all day and night-then, they're ready for the garden!
Whether you're moving your plants to a bigger pot or directly to the ground, it's essential to handle them gently during the transplanting process-their root systems are still fresh and delicate. If possible, try to transplant during the morning, on a cloudy day, to avoid shocking them too much. Soak the soil after planting to help them settle in. After a few days, you can treat them to a light dose of a high-phosphorus fertilizer to encourage root growth.
With these helpful seeding and transplanting techniques in your back pocket, you're already in for a great growing season! It's always a good time to start planning and prepping for your next spring garden-so remember to pick up some seed packets next time you stop into Plant Perfect!