Dahlias are hands down some of the most stunning and popular flowers you can add to your garden beds. Whether you call them Dahlias or use their old-school name, *Georginas*, there’s no denying the “wow” factor they bring. If you’re wondering how to get these beauties into the ground, I’ve got you covered with this step-by-step guide.
Timing is Everything
When it comes to planting, timing is the secret sauce. Dahlias are definitely not fans of the cold. Since they aren’t frost-hardy, putting them in the ground too early is a recipe for disaster—they’ll simply freeze, and all your hard work will be for nothing.
The best time to plant your dahlias outdoors is in the spring. You want to wait until the danger of a night frost has completely passed. For most of us, that sweet spot is usually late April or early May.
If Mother Nature decides to throw a curveball with a cold snap after you’ve planted, don’t panic! You can protect the young shoots with some garden fleece or even an upside-down black bucket. Without that protection, those fresh sprouts can get hit pretty hard by the frost.
How to Plant Dahlias: The Essential Steps
Ready to get your hands dirty? Here is the play-by-play on how to plant your dahlias correctly.
- 1. Prepping Your Overwintered Tubers
If you’ve stored your tubers from last year, give them a quick inspection. Remove any parts that look shriveled up or show signs of rot. If you have a massive, dense clump, it’s a good idea to divide it down to four or five healthy tubers. Make sure to cut them right at the “neck” (the root crown), because that’s where the eyes—the buds that actually sprout—are located. Even a single small tuber can grow into a beautiful plant! Of course, you can always just pick up fresh tubers from your local garden center.
- 2. Digging the Hole
Grab your spade and dig a hole in your garden bed. If you’re planting a row of them, make sure to space the holes about 20 to 30 inches (50 to 80 cm) apart. Dahlias need their personal space to grow big and bushy without getting tangled up with their neighbors. Plus, good spacing ensures that the leaves and flowers can dry off quickly after a rain shower, which keeps the plants healthy.
- 3. Finding the Perfect Spot
The ideal spot for your dahlias should have:
- Plenty of light (think sunny and warm)
- Rich, nutrient-dense soil
Good drainage is a must! If you’re dealing with heavy clay soil, mix in a layer of coarse sand. This helps the water drain away and keeps the soil nice and loose.
- 4. Planting and Covering
Place one tuber in each hole. Position it so the slightly curved neck is pointing straight up. You want to plant it deep enough so that it’s covered by about two inches (5 cm) of soil. The old stem from last year should just barely peek out of the ground once you’re done.
Here’s a little tip: the deeper you plant them, the better they are protected from a surprise frost, but they might bloom a bit later. Shallower planting usually leads to earlier flowers.
Also, it’s a great idea to stick a thin stake into the hole right now (be careful not to poke the tuber!). This gives those tall, heavy blooms something to lean on later in the season.
- 5. Water and Feed
The final step is a good soak. Dahlias are thirsty plants! They need plenty of water, especially right after planting. I also recommend a first round of fertilizer at planting time. This gives them the nutrients they need to hit the ground running and grow strong.
Pinching Back for Bushier Plants
If you’re starting with young or single tubers, they might only produce a few thin stems and a handful of flowers in their first year. To get a bushier plant with more blooms, you can “pinch” the stems. Just snip off the top of the shoot right above a pair of leaves. It might delay the first flowers by a week or two, but it encourages new stems to grow from the leaf axils, leading to way more flower buds in the long run!
Getting a Head Start (Pre-Sprouting)
Dahlias planted directly in the garden usually start blooming around July. If you’re impatient for those colors, you can pre-sprout your dahlias indoors. By planting them in pots in March, you won’t have to wait until mid-summer for the show to start. Just remember: these “started” plants are extra sensitive to frost. Wait until after the last frost to move them outside, and make sure to gradually acclimate them to the intense sunlight so they don’t get sunburned.
A Pro-Tip for Vole Problems
If you have voles in your garden, they can be a real headache for dahlia lovers. These little critters love to dig around and munch on the tubers. If you know you have a vole problem, try planting your tubers in homemade “baskets” made of wire mesh. It’s a simple way to keep your dahlias safe from underground snackers!
