What Is Indoor Seed Starting & Why Do It In January?
Indoor seed starting is the process of sowing plant seeds indoors in pots or containers. Typically, these seeds are kept in pots till seedlings emerge and outside conditions become more favorable for planting.
Many gardeners opt for indoor seed starting in January as it is one of the coldest months of the year and many areas experience frost and snow during this time which isn’t ideal for sprouting or even overall plant development.
Zone 1-3: Hardy Crops To Get Ahead Of Spring
Onions: Onions are a cold-season crop. However, instead of planting onion sets directly in the ground outdoors, consider first planting them indoors and later transplanting the baby bulbs outdoors when conditions get better.
Turnips: This root vegetable is personally my favorite hardy January crop. It’s cold-tolerant and should ideally be started around mid to late January and transplanted outdoors in March or April for the best and safest growth.
Leeks: While leeks typically prefer slightly warmer temperatures, starting them in January still isn’t a bad idea. They’re a versatile, cool-season crop that can make your fall and winter dishes great.
Carrots: Carrots are known for their frost-tolerant abilities. As a matter of fact, they thrive in frost and can become sweeter after undergoing a cold spell. Start them indoors in mid to late January and transplant them to the garden as soon as some warmth emerges.
Zone 4-5: Cool-Season Crops To Kickstart Growth
Spinach: Spinach — the classic leafy green that everyone loves for huge forearms (If you know you know). Start your spinach indoors in January to give it a headstart and get a jump on the growing season.
Lettuce: Another classic leafy green that can benefit from early planting. Start seeds late in January or early February and extend the growing season for better-tasting lettuce harvests.
Kale: Kale also becomes sweeter after undergoing spells of frost, but, like others, it needs to be started indoors in January if you want to give your kale a head start.
Zone 6-7: Balancing Cool & Warm-Season Plants
Peppers: Try starting your pepper seeds 5-8 weeks before the last frost date. They need some warmth to be able to grow at their best, so maybe try transplanting the seedling outdoors when conditions heat up.
Tomatoes: While tomatoes have a preference for warmth and heat for good growth, they can still thrive in zones 6-7 because of the moderate to cool temperature conditions.
Celery: Celery seeds should be sowed indoors early in January to give the plants a headstart and longer growing season. Generally speaking, 6-10 weeks before the last frost date works best.
Cauliflower: Another solid cool-temperature option that will thrive if started early in January. A light frost can help cauliflower develop a more appealing flavor.
Zone 8-9: Planting For Extended Growing Seasons
Squash: Start your squash seeds indoors ideally around the end of January. Because zones 8-9 offer milder temperatures, you don’t have to worry about cold damaging your squash seedlings. As warmth sets in, you’re good to transplant the seedlings outdoors.
Parsley: Many crown parsley as the ultimate garnish for savory dishes. Start the seeds in a small pot or seed tray around early January or Late December and let them germinate. Parsley takes some time to germinate but it’s usually ready to harvest in as little as 4-6 weeks.
Mint: Mint is a personal favorite. I enjoy mint in sweet and savory dishes, teas, and even fragrances. You can start mint seedlings early in zone 9 winters because the plants would appreciate a slightly cooler growing season.
Zone 10: Year-Round Crops For Warm Climates
Rosemary: To my nose, rosemary has to be the strongest, most pungent herb out there. But, that doesn’t mean it’s bad; I just find the aroma a little polarizing. Start the seeds indoors till the outside temperature heats up and then transplant the seedlings into the ground for the best results.
Thyme: For a solid spring harvest, definitely consider starting thyme seeds early in January and provide the seedlings with plenty of sunlight so growth isn’t weak or leggy.
Grapefruit: This delicious, juicy tropical fruit remains under the radar even to this day. Not many people care about grapefruit these days but those of you who do, just know I love all of you.
While you can sow the grapefruit seeds directly into the ground outdoors in zone 10 winters, late January or early February is typically the time to start the seeds if you wish to start them indoors first.
Essential Tips For Successful Indoor Seed Starting
Some seeds require intense lighting to carry out the germination process while others don’t. The seed package will typically have guidelines on how you should go about this aspect.
Water is important for the seed-starting process, but, while they do need the hydration, make sure to not suffocate or drown them with too much water.
Loose and airy soil generally works well for seed starting. Ensure it’s not overly compacted so the shoots can easily emerge and spread in the seed tray or pot.
