Do dahlias grow in Florida?

Do dahlias grow in Florida: fimbriated dahlias

Do dahlias grow in Florida? It is certainly a good question, because dahlias aren’t naturally suited to the year round heat and humidity that you’ll find in some parts of Florida.

However, it is worth remembering that Florida’s climate varies across the state. You can see this from the USDA plant hardiness zone map below.

The lowest minimum temperatures are in in the north (zone 8), where hard frosts can occur.

In central and south Florida, the climate is sub-tropical, bordering on tropical. Thus Orlando is in zone 9b, Miami is in zone 10b and some of the most southerly keys are in zone 11b.

Do dahlias grow in Florida: hardiness zone map

So, do dahlias grow in Florida? The short answer is yes. There are plenty of examples of it happening. But growing dahlias in Florida is not without its challenges and those challenges will vary according to where in Florida you want to grow dahlias.

Can dahlias grow in Florida’s cooler, northern parts? Yes, but you will have to think about the the effects of cold and frost and how you overwinter your dahlia plants and tubers. This post on how to grow dahlias will help you manage your Florida dahlias in these more temperate conditions.

Will dahlias grow in Florida in the hot southern parts of the state? Yes they will, but you’ll need to think about the effects of extreme heat and humidity in summer and how this effects the way you plant and look after the plants. In particular, make sure you choose heat tolerant dahlias to maximise your chance of success. We list more 120 heat tolerant varieties in this post: Heat tolerant dahlias: beat the heat with these 120 choice varieties.

If you are in the southern keys, you might want to read this post on whether dahlias can grow in a tropical climate. Otherwise, if you want some guidance on how to grow dahlias in Florida’s sub-tropical central and southern parts, this is where you’ll find the answers you need.

How can dahlias grow in Florida?

When you are growing and taking care of dahlias, it is always worth thinking about where dahlias come from and how your conditions differ from those that dahlias evolved in.

Dahlias are native to Mexico and other parts of Central America. Whilst these areas have hot summers, winters can be cool. Perhaps more importantly, dahlias typically came from elevated regions and grew in well-drained hillside locations. So in such places, temperatures drop at night, drainage around the dahlia tubers is good and light levels are high.

Obviously, the dahlias we grow today in our yards and gardens have been bred and cross-bred over the years. Therefore, most dahlia varieties, like the pompon dahlia Wizard of Oz for example, are quite visually different from dahlia pinnata, dahlia coccinea and dahlia imperialis, which were the species originally imported from Mexico to Europe.

Nevertheless, some of the fundamental requirements that dahlias have, such as frost free environments, good light levels and good drainage are reflective of where they originate from. And, if we are growing dahlias where conditions are somewhat naturally different, we need to bear these differences in mind if we want to succeed with these wonderful flowering plants.

Do dahlias grow in Florida: formal decorative dahlia

How to grow dahlias in Florida

Here are some of the key points to remember when thinking about how to grow dahlias in the hot/sub-tropical climates of central and southern Florida.

  1. Ensure the dahlias are planted in rich, well-drained soil with a pH level between 6.0 and 7.5. In the sandy soils of Florida, especially those in the central Flatwoods regions that can be poorly drained, it is important to amend the soils with well-rotted manure, compost or other organic matter to improve soil structure and drainage.
  2. Plant dahlia tubers deep – i.e. at least 8 to 10 inches (20 to 25cm) below the soil surface. This will protect the tubers and feeders roots from scorching heat.
  3. Additionally, apply at least a 2 inch (5cm) layer of organic mulch when the dahlias are planted. This will help keep the plants cool in the hot summer months.
  4. Us organic fertilisers and pest control methods, reducing your reliance on chemicals. Dahlias are strong, robust growers and respond well to an organic approach, performing well in soil with high organic content and without the need for chemical fertilisers. Use an organic potash to promote flowering when buds start to appear.
  5. Expect your dahlias to stop growing when temperatures are very high (over 90°C or 32°C). In regions where high summer is extremely hot, e.g central and southern Florida, the best growing season for dahlias are Fall and Spring.
  6. Try planting dahlias in September for blooms in November and December, and a second flush in Spring. This works in Orlando, Zone 9b.
  7. Grow your dahlias where they can get some afternoon shade to avoid exposing them to the worst of the scorching sun.
  8. Space your dahlias at least 12 to 18 inches (30 to 45cm) apart. This will help air circulation between plants and reduce the chance of fungal diseases, like powdery mildew. You can also remove some of the plants’ lower leaves when they have matured as this will also help the airflow around your plants.
  9. Mist your dahlias when the heat is extreme. You can set up an automated, timed, misting system or just use the mist setting on your hose nozzle to cool the plants down when it is extremely hot.
  10. Don’t forget, you still need to pinch out and deadhead dahlias, whatever the climate, in order to get more flowers for longer.

Potential problems when growing dahlias in Florida

Here are some of the problems you might face growing dahlias in the sub-tropical parts of Florida.

Heat stress

Dahlias like warmth and full sun – in temperate climates.

But when there is extreme heat dahlias can suffer – petals might burn, stems might wilt. This is why it is important to plant your dahlias in Florida where they can get some afternoon shade.

The shade of a tree is best, because trees naturally cool the air surrounding them through the process of transpiration (giving off water vapour). But if you have no natural shade available, rig up some shade cloth or netting that you can pull across the plants when needed.

As mentioned above, it is also a really good idea to mist the dahlias with water spray when temperatures get really extreme.

Fungal diseases

High humidity and rainfall can cause dahlias to suffer from bacterial and fungal diseases, such as:

  • Bacterial wilt which cause the stems to rot. You’ll need to destroy any affected dahlias.
  • Bacteriosis which also attacks the stems causing them to brown and rot but can also attack the roots. Remove damaged plants.
  • Botrytis blight which rots the buds and creates a grey mould. Remove damaged parts of the plant.
  • Powdery mildew which attacks the leaves and leaves a white powdery mould on them. Remove affected leaves quickly, improve watering at the roots.

To deter fungal disease, space plants at least 12 inches (30cm) apart. You can also remove some some leaves from the plant, but leave enough to ensure the plant can still photosynthesise.


According to the University of Florida, you need to look out for Aphids, European Corn Borers, Stalk Borers, Leafhoppers, Thrips and Mites.

Best dahlias for Florida

One of the most critical things to do when growing dahlias in Florida is to choose heat tolerant varieties. Examples include:

  • Aitara Caress – cactus dahlia, pink and white
  • Camano Messenger – cactus dahlia, pink and yellow
  • Clara Huston – cactus dahlia, orange
  • Hilcrest Kismet – formal decorative dahlia, pink and yellow
  • Just Peachy – semi-cactus dahlia, pink and yellow
  • Peaches ‘n’ Cream – formal decorative dahlia, orange and white
  • Robann Royal – miniature ball dahlia, lavender
  • Thomas A Edison – formal decorative dahlia – purple

We have a lot more on heat tolerant dahlias in this separate post.

More on growing dahlias

You can also get much more guidance on growing dahlias in these posts:

Love Dahlias?I've written the book on them

Check out my comprehensive step by step guide, with plain language explanations and ultra-useful images and illustrations. This is for you if you love dahlias and want to the best out of the dahlias you grow.

Join Us! Subscribe to the Gardening Step by Step NewsletterSign up below to receive the latest gardening tips and updates*

*by entering your details, you're agreeing to the terms and conditions and privacy policy. You can unsubscribe at any time.

Leave a Comment