If your garden looks tired at the end of the season, but your neighbors’ is full of color and texture, chances are they may be growing dahlias. Dahlias bloom from mid summer until frost, and come in small bedding sizes to large 3 foot plants with dinner plate size blooms. They are easy to grow with a few basic guidelines and tips, and will bloom when few other things in the garden will. Did I mention they are gorgeous? Great cutting flowers and pretty in the garden. What more could you want? Here’s how to grow dahlias, the easy way!
How to Grow Dahlias
- Dahlias are most often grown from tubers (like bulbs) planted in the spring. If you want the best varieties though, be taking notice of the plants that are blooming in early fall, and take note of the variety. One way to do this is to visit a nursery and check out plants in pots. I don’t recommend planting them from pots in the fall… they just aren’t a good value for the time they will bloom before frost. Start them in the spring for a longer bloom time and healthier plants.
- Choose tubers that are healthy and starting to sprout, or order online from a good quality company.
- When to plant dahlias- Plant in late spring after the soil is warm in full sun… don’t plant too early. A good rule of thumb is to plant dahlias when it’s safe to put tomato plants in the ground.
- Plant in rich, well drained soil, so that the crown is just below the soil. Don’t water until they start to sprout out of the soil They are prone to rot.
- For tall or dinner plate varieties, put several stakes around the plant. That is so that you can secure the heavy plant as it grows. Tomato or peony cages are good for this also, depending on the size you are growing.
- Fertilize every two weeks with a bloom fertilizer. Its important that you use a fertilizer low in nitrogen, (thats the first of the three numbers on a fertilizer) because too much nitrogen will grow big plants with no blooms.
- Keep well watered, but try not to water late in the evening, especially later in the fall. They can develop powdery mildew. if your area is prone to mildew (on roses, for instance) then you can use a commercial or natural anti fungal spray starting in July to prevent it.
- When your plant is 6-8 inches tall, pinch off the top growing point above the third set of leaves to encourage a bushier plant. Remember to clip off dying flowers at least once a week to promote more blooms.
- Dahlias can be hardy down to zone 7, but are usually treated as an annual.
- Learn how to store dahlia bulbs. If you want to lift your tubers and save them to replant next spring, do so before the first frost. Cut them back to 6 inches, and use a fork to gently pry them from the soil. Let them dry out for a few days, then store them in loose sawdust or vermiculite in an area that doesn’t freeze, such as an insulated garage.
- To cut dahlias, cut them in the early morning hours. BHG has this tip for making the blooms last… “After you’ve harvested dahlia flowers, make a fresh horizontal cut at the bottom of the stem and place the cut ends in about 2-3 inches of very hot (not quite boiling) water. Let the stems stay in the water for at least one hour. This hot-water treatment conditions the stems so the blooms will last four to six days.”
That’s it! Not that you know how to grow dahlias, here are some of our favorite varieties, both large and small! We recommend Swan Island Dahlias for ordering the best varieties online. Here are some of their choices…
Types of Dahlias We Love
Dreamcatcher – Grows to 4 feet with 6 inch blooms… This dahlia is a focal point for the garden!
Tahiti Sunrise – This spiky bloomer is a smaller plant, about 2 1/2 feet tall, with 5 inch blooms.
Bonne Esperance – A variety from the ’40’s, this single blooming pink beauty shows you that not all dahlias are of the double appearance… Low growing to 12 inches, this blooms early and long for a charming bedding plant!
Emory Paul – This is a large, dinner plate dahlia variety, growing to 4 1/2 feet tall, with blooms over 10 inches across! Support is a must for this variety that is often used for exhibition. Color is amazing!
Bridezilla – Dahlias can be just as stunning without all the flashy color… this white variety with a yellow “eye” would be gorgeous in any garden and would make a wedding bouquet worthy cut flower. Tall, at 5 feet plus, the blooms are 6 inches across. My fav!
We are planning on ordering a few of these for our garden now that we know how to grow dahlias! Pin your favorites for later! Jump on over to our posts on How to Grow Peonies and How to Grow Hydrangeas!