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Explore Your Local Garden Center at a Home Depot Near You. Get inspired to upgrade your plants and landscaping.

Garden Center

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Pro Service Desk(720)733-3464
Tool & Truck Rental(720)733-3470
Store Hours
Mon-Sat: 6:00am - 10:00pm
Sun: 7:00am - 8:00pm
Curbside: 09:00am - 6:00pm
Location
333 W Allen St
Castle Rock, CO 80108
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Frequently Asked Questions About Gardening

Which planting zone am I in?

Check the USDA planting zone map, as planting zones have changed slightly over the years. Planting zones with higher numbers can plant earlier in the year. Increase your odds of successful gardening by choosing plants that are meant for your zone.

What does direct sow mean?

If the soil is warm and pliable, consider planting your flower, fruit, or veggie seeds directly into your garden. This is called the "direct sow" method. The time to plant will be after the threat of frost is gone for the season, as seedlings and sprouts can't weather those conditions. You can also start your seeds indoors if you'd like. Consult your seed envelope for when and how to sow seeds.

Do you carry organic seeds and plants?

Yes, we've got a variety of organic options, including organic veggie seeds and fruit seeds, and organic flower and herb seeds that are subject to availability. We carry the organic soil to plant it in as well as the organic fertilizer to feed it.

Should I harden off my seedlings before planting them outside?

Yes, for best results, if you raised plants indoors from seeds, harden them first before you transplant them. Hardening allows your seedlings to adjust to outdoor life and the fluctuating spring weather, making them more resilient against cold snaps. It slows their growth until they're strong and ready to take off during a spring warm front.

How do I prep for planting transplants or seeds outside?

Before you plant, make sure that the soil is healthy, your plant will have the right amount of sun, and it's warm enough outside. Check your seed envelope to see if it likes shade, full sun, or partial sun, as well as what time of year it should be planted. Space your plants as described for best results so your plant babies have room to flourish.

Should I use peat moss starters or coir starters?

Seed starters, full of nutrients in pots or pellets, work for new and experienced gardeners. You don't have to use these starters if you're planting in soil, but you may want to. Starting seeds in peat pots works best for delicately rooted plants like carrots and beets, as well as flowers that require an acidic pH. Some people prefer coir starters instead, as they have a neutral pH. Check what type of soil your plants need to help narrow it down, and chat with a garden center associate if you need more info.

The Home Depot Garden Center at Castle Rock

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

Plant Hardiness Zones Explained
The first thing to learn when planting spring flowers, veggies, and other seeds is your planting zone. Every location in the U.S. and its territories is sorted 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. For best results, choose plants in your zone number or less. In other words, a Zone 9 garden can support plants listed as Zones 1–9. The timeframe to direct sow outdoors in your garden is often around a month later than the indoor start date. Always read your seed packet for details. If you start seeds a little later than recommended, it's not ideal, but it will 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 can have extreme conditions, so consider indoor gardening as a strong supplement to growing outdoors if possible.

In the desert, native plants like cacti, succulents, 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 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, waiting until the frost has passed will give your seeds the best chance at a hearty and healthy life.

Check out certain herbs and cruciferous veggies if you’re ready to get planting. This includes cabbage, broccoli, and kale. Greens like spinach, artichokes, 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.

Plant Seeds Outside With Direct Sow
Planting seeds into your garden soil, or using the direct sow method, is an alternative option. There's less tending and planning than growing indoors. If you like to go with the flow, follow the instructions on your seed package and give it a try.

Your seeds might get washed away or struggle to grow, or bugs or critters might eat the sprouts. But if you're really fortunate, you might get a strong sprout from each place you sowed seeds, perfectly spaced and ready to grow all spring. The reality of your sown seeds will usually be somewhere in between, and spreading out tiny sprouts throughout the soil isn't so bad. You know those sprouts are primed to survive and hardy, although there are no guarantees.

Start Seeds Indoors
If you'd like more control over your seedlings' journey or you're eager to get growing, start your seeds indoors instead. In general, you can plant seeds indoors about a month before you can do it outside. Like direct sow, you push the seeds into the soil as directed on the seed packet, but that's where the similarities end.

You're responsible for giving them quality substitutes for rain and sunlight. Keep your seeds cozy with warming mats and grow lights, water them carefully with a mister or watering can, then thin them as they germinate in groups of three. Give them a boost with a gently blowing fan as they lengthen into sprouts if you'd like. Harden them off to get them used to outdoor conditions, then transplant them into your garden when they're big enough.

Transplant Young Plants Into Their New Homes
Place your transplants in the ground, then give them a generous drink without overwatering. Blanket the surrounding area with mulch, marking where the plant is with a stick so you can easily find it among the grass clippings, old leaves, or straw. Consider putting up chicken wire or other protective measures if rabbits, squirrels, deer, or chipmunks visit your yard regularly, as your sprouts may otherwise become a snack.

Protect Your Garden With Mulch
Finish it off with compost and mulch. Mulch controls weeds and keeps the soil moist. Compost enriches the soil so your garden can grow even better. It may help foster larger and stronger plants that bear more flowers and fruit. 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. Prepare to fertilize your lawn, plan your garden and landscaping, and browse our garden center pages to find inspiration on which spring flowers to plant when the weather warms. Shop for the fertilizer, seeds, and soil you need in the aisles of your Castle Rock Garden Center, online, or on our mobile app. Let's get growing together.

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