Welcome to January in zones 4-6 – when your garden thermometer seems stuck somewhere between “brr” and “why do we live here?” With temperatures plummeting from a chilly -30°F to a still-pretty-chilly 20°F, your garden is definitely in hibernation mode. While our friends in warmer zones are already planting their spring peas (show-offs!), we’re huddled inside, watching the snow pile up and wondering if we should order one of everything from those tempting seed catalogs.

But here’s the thing – January doesn’t have to be just about staring longingly out the window at your snow-covered garden beds. Sure, we can’t dig in the dirt outside, but that doesn’t mean our green thumbs have to get frostbite. This is actually the perfect time to flex those gardening muscles indoors and get a jump start on the growing season. Last month we talked about microgreens on your windowsills, sprouts, and herb gardens under grow lights, but this month we’re working on early seed starting if you’re feeling ambitious!

What to Plant Indoors in January

While it’s still too early to start most vegetables, there are a few early seeds you can start for spring in January and should be started 10-12 weeks before the last frost, which for these zones is mid April to May.

1. Onions

• Start seeds 10-12 weeks before the last frost
• Provide bright light to prevent leggy seedlings
• Keep soil temperature around 70°F (21°C)
• Varieties like ‘Walla Walla Sweet’ and ‘Red Brunswick’ do well when started early

Onions need a long growing season, which is why we start them so early indoors. Sow seeds about ¼ inch deep in a quality seed starting mix. Once seedlings emerge, keep them under strong light for 14-16 hours daily – this is crucial for developing strong plants. When seedlings reach about 5-6 inches tall, trim them back to 3 inches to encourage thicker growth. Don’t worry – they can handle this haircut! Maintain consistent moisture but avoid waterlogging. Feed with a diluted liquid fertilizer every two weeks once they have their second set of true leaves. Plan to transplant these hardy seedlings outside about 2-3 weeks before your last frost date.

Growing celery

2. Celery

• Begin 10-12 weeks before last frost
• Needs consistent moisture
• Temperature should be 70-75°F (21-24°C)
• Try varieties like ‘Utah’ or ‘Tall Utah’

Celery is notoriously slow to germinate, often taking up to two weeks, so patience is key! Sow seeds barely covered with soil – they need light to germinate. Keep the soil surface consistently moist using a spray bottle to avoid displacing the tiny seeds. Once seedlings emerge, they need steady temperatures and high humidity – try covering them with a clear dome or plastic wrap. Celery seedlings are heavy feeders, so start fertilizing with a diluted liquid fertilizer when they have their first true leaves. They’ll need gradual hardening off before planting outside, as they’re sensitive to temperature changes.

3. Leeks

• Start 10-12 weeks before last frost
• Similar care to onions
• ‘American Flag’ and ‘Giant Musselburgh’ are reliable varieties

Leeks are like the patient cousins of onions – they grow slowly but reward you with incredible flavor. Sow seeds ¼ inch deep in cells or flats filled with seed starting mix. Like onions, they’ll emerge looking like tiny grass blades. Once they reach about 6 inches tall, trim them back to 4 inches to encourage thicker stems – you can add these trimmings to soups for a mild onion flavor! Keep the soil consistently moist and feed every two weeks with diluted liquid fertilizer once they have their second set of true leaves. When transplanting outside, plant them deeply (about 4-6 inches) to get those prized white stems.

Essential January Garden Tasks

Let’s be honest – there’s not much growing in zones 4-6 when it’s negative twenty outside! But January isn’t just about dreaming over seed catalogs (though that’s definitely a highlight of these cold winter nights). While your garden snoozes under its snow blanket, there’s still plenty to keep a gardener busy.

First up: get organized. Sort through those seed packets cluttering your drawer – you know, the ones you impulse-bought last spring? Check expiration dates, make your wishlist for this year’s garden, and order early. Those popular varieties have a way of selling out faster than concert tickets! It’s also time to show your tools some love. Clean and sharpen those crusty pruning shears, oil those wooden handles, and finally organize that chaos you call a garden shed.

Keep an eye on your winter garden too. Brush heavy snow off those evergreen branches (gently – nobody likes a face full of snow), and check on your sleeping perennials. Make sure hungry rabbits and deer haven’t turned your fruit trees into a winter buffet. Inside, your houseplants need attention – check for pests, wipe those dusty leaves, and resist the urge to overwater. They’re taking a winter rest too!

Most importantly, use this quiet time to learn and dream. Dive into gardening books, join some online garden groups, or start plotting your spring garden layout. After all, the best gardens start with a good plan and a winter full of dreams. Now, who’s ready to order some seeds?

Remember, while January might seem quiet in the garden, it’s actually setting the stage for a successful growing season. Use this time to learn, plan, and prepare – spring will be here before you know it!

What indoor gardening projects are you tackling this January? Are you trying any new varieties this year? Drop a comment below, and let’s keep our gardening dreams alive during these cold winter months!