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Try underused dahlias in summer landscapes
In my travels visiting garden centers and greenhouses, I’ve been reminded of plants that we don’t grow enough in Mississippi. Dahlias are on that list.
I can’t decide if it’s because gardeners think these beautiful plants need an extraordinary amount of care or they’re just not aware of them, but we need to grow more dahlias.
Dahlias grow from bulb-like structures that resemble sweet potato tubers. They are easy to grow, and if you can grow tomatoes, you can grow dahlias.
A good rule to follow is to plant your dahlia tubers directly into the garden when you plant your tomatoes. In other words, plant when the landscape soil has warmed and there is little chance of frost. Dahlias planted this way will typically bloom from midsummer through fall.
If you want flowers earlier, you can start tubers indoors under lights about a month before planting. This timing is similar to how you can start tomato seeds about a month before transplanting them into the garden.
Starting your plants can be problematic for many gardeners, but that doesn’t mean you can’t have early-flowering dahlias. Almost every garden center has a good selection of already blooming plants. Talk about instant impact.
Some dahlia varieties can be over 4 feet tall, but I like the smaller selections that can be grown in containers and enjoyed on the porch or patio. I really like the Dahietta dahlia series with their small, compact growth habits. This series has many unique colors and flower forms that only grow 8 to 10 inches tall.
Dahlias require care similar to what you give many other landscape flowers that grow in full to partial sun. In Mississippi, I suggest planting in a site that has good drainage; this is where growing in containers is a great idea. Dahlias need to be deadheaded to promote continued flowering through the season. Deadheading also helps them maintain their bushy, compact plant growth.
Dahlias are perennial, and the normal recommendation is to dig up and store the tubers after the onset of cold weather. For dahlia grown in containers, prune the stems at the top of the growing mix and store in the garage or other cool, dry location.
If they are grown in the landscape, prune the stems at ground level and mulch with about 12 inches of pine straw. Either way, dig up and divide the tubers the following March and replant when you transplant your tomatoes.
I prefer to use dahlias as annual color, and I just leave them out, providing no special winter protection. I do this with most of the color plants I grow. This way, I’m always surprised when some plants come back the following year.