Dahlias in Florida?
That’s right, you can grow Dahlias in Florida. The Beautiful tuberous plants are native to Mexico and Central America, with warm days and cool nights. The Extreme heat, heavy winter rains, pests and disease pose challenges when growing in hot and humid climates.
A few years back I attended a Dahlia workshop at a farm about 2 hours away. My husband and I spent the morning learning tricks to grow these tubers here and digging and dividing our own tubers to take home. They had success using grow bags to not only keep the roots cool in the height of summer, but to control the amount of moisture the plant receives. The Root Pouch fabric bags are made of recycled plastic bottles, which is pretty awesome. They allow the plants roots to breath, and excess water to drains out. I also read an article ( click to read it, from Jacksonville.com) about growing Dahlias in Northeast Florida. It mentions some of the same challenges I have had, but gave me hope.
Planting
Equipped with my new knowledge and determined to grow these gems I decided to try again with grow bags. I ordered Root Pouches, Dahlia tubers, and mix to fill the bags. I use a mixture of 1/3 Peat moss, 1/3 Perlite, and 1/3 compost for good drainage in the grow bags. Recommended planting times for zones 8-11 are October, January and March. You want to plant before it gets too hot. Plant the tuber at a 20 degree angle with the neck facing upwards with the eyes exposed. Cover the neck of the tuber with soil. You can add a plant tag so you’ll know which is which later on. Do not water until you see growth coming out of the top. Once about 6 inches of leaves are showing you can add mulch. They are winter Hardy in zones 8-11. This means you do not have to dig and store them in the winter like they do in cooler regions. They can be left in the ground, or grow bag through winter. You’ll just want to make sure they don’t get too much moisture during this time or they will rot. Its recommended to add a good layer of mulch once they are cut down around the first frost. ( If we get a frost!)
Support and Protection
Be sure to provide support before they take off. Some of mine are taller than me! They can get big and blooms are heavy. You can use a t-post or tomato cage with a single bag or pot. I use t-posts at the ends of a row of bags and tie string from both ends, similar to a Florida weave. They also may need additional fertilizer through the growing season, I apply a foliage feeding every few weeks and stop a few months before winter. I also grow under a hoop house that is covered in plastic to protect from the rain and shade cloth to keep the heat down. I added some misters above the bags to turn on in the afternoons to bring the temperature down. Inspect daily for signs of pests or diseases. If pests become an issue when blooming, place organza bags over the bloom and pull strings closed to keep any critters from chewing on the delicate blooms.
How to choose which varieties to grow? They are all so beautiful, there are small ball type to large fancy dinner plates. Some are more heat tolerant and are recommended for hotter climates. The plants with large blooms usually are less heat tolerant. The Georgia Dahlia Society has a list of recommended heat tolerant varieties. Make sure you get quality tubers. I order mine from a Flower Farm in Maine, Skyfall Flowers.
So if you’ve always wanted to grow Dahlias in Florida, don’t be scared to give it a try! Happy growing!