Master the Art of Seed Starting: Insider Tips for Thriving Cold-Tolerant Crops

When you think about winter activities, gardening may not be the first thing that comes to mind. But you have a wealth of cool weather crop options available to you, from leafy greens to herbs. 

In many cases, the key to winter gardening success boils down to what you do during the plants’ earliest stages when they’re most vulnerable to harsh conditions. This is when seed starting can make a difference.

Seed starting is the process of planting and caring for seeds in a controlled environment before transplanting the resulting seedlings into your garden beds. This process fosters healthy root growth and increases seedlings’ chances of thriving when they’re in the ground.

Seed starting is a great way to set up many — but not all — cool season plants for success. 

“A lot of your root crops like carrots, turnips, and beets need to be planted directly in the ground,” Vego Garden Horticulturist Carol Childres said, adding that transplanting these plants from a seedling tray to a garden bed poses the risk of damaging them.

But leafy green plants like kale, collard greens, chard, and lettuce can benefit from seed starting, along with broccoli, cauliflower, onions, garlic, and many other cold-resistant vegetables. Seed starting can also be a good choice for cool season herbs including parsley, dill, fennel, and cilantro.

Do a Bit of Research

Before seed starting, Childres suggests investing time in some research to identify the best winter plants for your region, along with the optimal planting timetable and environment for them. Seed starting should begin about six to eight weeks before you plan to transplant seedlings to your garden.

“You can go to your county extension agent’s website, and in a lot of cases they have really good vegetable planting guides,” Childres said. “The seed packets are great sources of information, too.”

Seeds, Containers, and Planting Materials

Keep in mind that fresh seeds that have been stored in a cool environment are most likely to germinate (develop from a seed to a plant) and produce healthy crops. 

Your choice of planting container is up to you; just aim for something with drainage holes. 

A warning: Containers that have held soil are likely contaminated with fungus that could impact your seedlings’ health. Sterilize the containers with a bleach solution and rinse thoroughly.

Along the same lines, Childres recommends a sterile planting mix for seed starting. You can buy one or make one with equal parts of vermiculite, perlite, and peat moss.

Gradually place layers of mix in the containers, add warm water, and give the material time to slowly absorb the water. You want the mixture to be moist, but not soaked. Don’t pack in the soil too tightly: The seedlings’ roots need airflow and space to grow.

Adding Your Seeds

When you plant your seeds, refer to your seed packets for optimum planting depths.

From there, you’ll need to cover your containers and label them.

You won’t necessarily need to water the seeds before they germinate. The covered containers trap water in the air and promote a moist environment, but it will be important to check them to be on the safe side. Keep the seedlings in a safe location away from pets and drafts.

After Germination

Once you see green shooting above the planting material, you’ll need to provide light 12 hours a day for the remainder of the seed-starting process. LED plant lights with timers can be a good option. Keep the lights about six inches above the seedlings.

Spray your seedlings’ planting material with water regularly to keep it moist — but not soaked.

Hardening Seedlings for the Cold

To increase your seedlings’ chances of enduring harsh winter temperatures you can add a step before planting them in your garden. Transplant the seedlings to larger pots where their leaves and roots can grow more. 

Hold seedlings by their leaves, not their stems, when you transplant them. Childres plants the seedlings in an organic soil mix and begins providing fertilizer.

You’ll need to continue to provide light, moisture, and optimum temperatures during this intermediate stage.

This is a great time to gently introduce real-world conditions. By running a fan, you can prepare your seedlings for outdoor breezes.

Graduation!

After about two or three weeks, the seedlings should have thriving leaves and roots, and they’ll be ready to move to your outdoor gardens.

Your plants will still need your ongoing care — and you may have to cover or move them in cases of severe or prolonged freezes.

But, generally, by your strategic seed starting, you will have set the stage for successful winter crops.

Visit Vego Garden’s seedling tray suite to help you sow those seeds!