The Best Options for Staking Dahlias
Not all dahlias need support. But staking is a must for varieties that grow more than 3 feet tall. Though dahlias can develop stalks as thick as broom handles, they have a significant design flaw. Their stems are both hollow and brittle. A large, unsupported side branch, a thunderstorm, or a waterlogged flower head can split a plant in two.
The best time to stake or cage your dahlias is shortly after planting. This way, you won’t accidentally damage the tubers when inserting the stakes. But even if you don’t get around to providing support until the plants are a couple feet tall, it’s definitely still worth doing.
Three Strategies for Staking Dahlias
Individual Stakes. The best way to avoid broken stems, and keep your dahlias neat and orderly, is to stake each plant individually and tie-in the branches in as they grow. Position the stake about 3″ away from the center to avoid damaging the tubers. As the plant gets taller, tie the main stems to the stake, leaving just a little slack so they can move around and absorb some of the wind’s energy.
Use this technique if you are adding individual dahlias to a perennial garden, planting them in the landscape, or growing them in containers. If you are growing a large number of dahlias in rows, as in a cutting garden, staking each plant is time-consuming and can also get quite expensive. Read on for some other options.
Corral Method. For this approach, you’ll need some hardwood stakes and at least one ball of garden twine. (See below for more information about various types of stakes.) Place the stakes at 3 to 4 foot intervals along both sides of your dahlia bed. Pound them in 10- 12″ deep. While it may be tempting to use fewer stakes and space them further apart, you will find that over time, the twine gradually sags and does not provide adequate support.
Install the first row of twine when the plants are about a foot tall. This lowest row should be 12-18″ off the ground. As the plants get taller, encircle them with additional twine at 12″ intervals. If you grow dahlias in the same place each year, you may be able to leave the stakes in place from one growing season to the next.
Corral With a Web. This is a deluxe version of the corral method. The twine encircles the plants and also criss-crosses the row for added support. Since my dahlias are planted in wide beds, I find this extra support is very helpful. Adding a row of stakes down the middle of the bed will help you create an even sturdier web.
Once all the stakes are in place, use twine to encircle the plants as in the corral method. Then turn back to cross the row on diagonals, wrapping twine around the center post along the way. (See photo above).
What to Use for Stakes
Options include hardwood stakes, bamboo canes, plastic-coated steel stakes, and T-style steel fence posts. Though purchasing stakes can get expensive when you’re starting out, they should last for many years.
Wood Stakes. For mid-size dahlias you can get away with 1″ x 1″ hardwood stakes. For taller plants, you’ll be better off with 1″ x 1-1/2″ or even 2″ square hardwood stakes. They should be 5 or 6-feet long so you can get at least a foot into the ground. If you are using the corral method, consider bulking up the corners with 2″ square hardwood stakes.
Bamboo Canes or Plastic Coated Steel Garden Stakes. These work well, are easy to handle and last for many years. For large plants, you’ll need 5 or 6-foot poles that are at least 1” in diameter. If you are only staking a couple plants, consider giving each of them two poles, positioned on either side of the plant (see photo below). This will give you more tying options as the plants get larger.
Metal Rebar. Purchasing rebar and cutting it into 6′ lengths is quite a project, but you can pass your dahlia stakes onto future generations! Rebar is also very easy to pound into the ground, even in dense, heavy soils. Use one stake per plant as you would for the wooden ones. If you’re using the corral method, you could use wood stakes for the sides of the row and rebar stakes at the ends.
Two Other Support Options
Tomato cages. This is an easy way to support individual dahlias. Square tomato cages that fold flat for storage are ideal. The round ones work OK if you make one modification. Use bolt cutters to cut off the legs and then position the cage so the wide end is resting on the soil surface. This gives the cage a more stable base. Anchor it in place with metal ground staples or tent stakes. Match the height of the cage to the mature height of your dahlias. For dahlias that grow more than 4′ tall, you may be able to find a jumbo tomato cage or another type of commercially-produced plant support.
Remesh or Concrete Reinforcing Wire. This material is a grid of thick, welded steel wire that ages to a rusty brown color. You can find it in big, 4×8 sheets at home centers and lumber yards. Transporting it is not easy. Cutting and bending it is even more difficult. But concrete reinforcing wire can be made into terrific dahlia supports that are strong, very long-lasting, and nearly invisible. (You can also make custom supports for peonies, delphiniums and hollyhocks.) Storage is a bit of a problem as they don’t collapse. But since they are practically invisible, I often leave them right in the garden.
Proper Staking is Always a Good Investment
Making sure your dahlias are well supported will ensure they look their best and give you as many flowers as possible. You’ll also find that keeping the plants tidy and well supported makes it easier to keep up with in-season maintenance tasks like harvesting and deadheading. And, when your dahlias are up off the ground, it minimizes pest and disease problems.
It may take some experimenting to find the staking solution that works best for your garden. But once you do, you can look forward to many years of beautiful blooms.
You can shop for dahlias HERE. To learn more about growing dahlias, you may be interested in these articles: