Garden Center at Westminster, CO #1517

It's time to start thinking of spring. We're here to help you prepare for sprouts poking up, fragrant breezes, and warmer temperatures. Planting seeds indoors with grow lights means you'll be ready to transplant young veggie plants and spring annuals when the frosts are through and the ground thaws. You might even want to directly sow organic seeds into the earth.

Plant Hardiness Zones Explained
The first thing to learn when planting veggies, spring flowers, and other seeds is your planting zone. Every location in the U.S. and its territories is sorted into blocks by climate. Find your zone on the USDA planting zone map and learn when to plant seeds.

For example, you could plant bell pepper seedlings outdoors in mid-March in Zone 10, but not until the end of May in Zone 4. You'll have good results with plants that have your zone number or less. In other words, a Zone 5 garden can support plants listed as Zones 1–5. You can plant seeds indoors roughly a month before you can plant them outside, or direct sow. Read your seed packet for details. If you start them later than recommended, it's not ideal, but it will likely even out as time passes.

Gardening in Your Growing Zone
The diverse topography of this area means planting times vary widely. Desert areas are in Zones 7-10, depending on location, and areas with more elevation are in chillier Zones 4–6. Both mountains and deserts are susceptible to extreme conditions, so consider indoor gardening as a strong supplement to growing outdoors if possible.

In the desert, native plants like succulents, cacti, and other hardy desert shrubs will grow outside with ease. Other beloved garden vegetables love the heat, like nightshades. If you start them indoors and carefully introduce them outdoors in the shade, you can enjoy raising vegetables even in a dry climate. However, many flowers, both annuals and perennials, are sensitive to that much sun and heat, so research to find which varieties can handle the weather before planting outdoors.

Colder regions in Zones 6–8 should wait a little longer to plant, and all these zones need to wait an additional month before planting seeds outdoors rather than indoors. Mountainous regions in Zones 3 to 5 will have the shortest growing season, with seed starters going in later in the spring. Although the weather may vary, wait until the frost has passed to give your seeds the best chance at a healthy life.

Check out cruciferous veggies and certain herbs if you’re ready to get planting. This includes broccoli, cabbage, and kale. Greens like artichokes, spinach, and fragrant herbs, including basil, parsley, and oregano, also don't mind an early beginning. In Zones 4–6, traditional garden vegetables like peppers of all kinds, cucumbers, and tomatoes are fine with an early spring or late winter start indoors under the grow lights.

Start Seeds Indoors
Grow your garden from seeds by starting them indoors. We've got all the seed starter supplies you'll need. For best results, you'll want grow lights or a warming mat to go with your seed tray or plant pots. If you're planting a larger garden, use seed trays — like the ones you see sprouts in at your Westminster, CO Garden Center — to make it easy to stay organized and plant tiny soil plugs later. You can also use pots with seed starter mix and potting soil.

Measure your finger to use it as a ruler. In general, you'll plant 3–5 seeds, then press them into the soil to the depth you need with your finger. Mark where you planted the seeds with a plant tag or toothpick. That way, you'll know where your seeds should pop up. Otherwise, it'll be a surprise when the sprouts push out of the soil.

Sprouts
Prepare your seed sprouts for outdoor life while they're still indoors. These inch-tall micro-seedlings are fragile but resilient. Seedlings certainly don't get all this pampering in nature, so they can handle more than you think. However, don't go overboard, as your sprouts are still babies. You can even use an oscillating fan on low to mimic the wind and strengthen their stems.

Harden Your Seedlings
Harden your seedlings for strong plants. On days above 45 degrees, take your pots or trays of seedlings outside to slowly warm in the shade for two hours, but bring them inside at night. They're not ready for direct sunlight yet or harsh nighttime temps. Gradually add more outside time each day, incorporating a little sun to get your plants used to it. After a week or more of this, you can leave them out overnight if the temps stay warmer than 50 degrees. Cover your plants if they're in the ground and a late-season frost sneaks back in.

Transplant Young Plants Into Their New Homes
Place your transplants in the ground, then water them well. Blanket the surrounding ground with mulch, marking where the plant is with a stick so you can easily find it among the grass clippings, old leaves, or straw. If your yard is regularly visited by rabbits, squirrels, deer, or chipmunks, consider putting up chicken wire or other protective measures so your plants and veggies are less likely to get eaten before they thrive.

Protect Your Garden With Mulch
Finish your planting by following it with compost and mulch. Compost enriches the soil so your garden can grow even better. It may help foster stronger and larger plants that bear more flowers and fruit. Mulch keeps your soil moist and controls weeds. Compost and mulch can be DIY creations, but you can also purchase them in-store. The next time you're looking for "mulch near me," stop by the Garden Center to get the right amount.

Greet the Spring
Early spring is an exciting time in the world of gardening. Don't miss a minute of growing season. Plan your garden and landscaping, prepare to fertilize your lawn, and browse our garden center pages to find inspiration on what to plant when the weather warms. Shop for the soil, fertilizer, and seeds you need in the aisles of your Westminster, CO Garden Center, online, or on our mobile app. Let's get growing together.