Dahlias- they can be a diva in the garden but also in the vase! Yet, we keep growing them because they are just that fabulous! However there are a few tricks to getting great vase life!
How to achieve the best vase life possible out of your dahlias:
1. Expectations- It’s important that we know what to expect out of dahlias so we know what’s possible. Dahlias are definitely more of the “here for a good time, not a long time” type of flower. They will put on a show and then suddenly just be done. (But this means you just cut some more for your vase).
Average vase life for a dahlia is 4 days. This average is based on numbers from experimenting with dahlias cut during extreme heat and also during cooler weather. Why? Because the weather has a big influence on vase life. Dahlias cut during a heat wave live 2-3 days in the vase, dahlias cut in mid October during a cool period live 6-8 days in the vase. Knowing what is expected helps to achieve the maximum possible.
2. Plant Health- Healthy plants produce higher quality blooms that achieve better vase life. Better vase life is one of the many reasons to keep up with your pest control, disease management, and fertilizing. A struggling plant is going to produce a stressed bloom which will die faster in the vase.
3. Harvest stage and time- You’ve probably heard that time of day is important when cutting flowers and it absolutely is! Early morning or evening is best to cut flowers. Flowers cut when they are less stressed by the weather will hydrate faster and more completely. Blooms cut in the high heat of the day struggle to catch up and have a noticeable difference in vase life.
Bloom harvest at the correct stage also have a longer vase life. This stage varies a little bit for the specific form of dahlia. But generally speaking about 40-50% open is ideal. Dahlias will open about 20% more in the vase so you want to cut at a fairly open stage but not so far that the bloom is blown completely open. If you see the pollen at the center of your dahlia already getting fuzzy - it’s definitely too late to cut for good vase life.
4. Cleanliness- A clean container and clean water- Always wash your bucket, vase- whatever you are harvesting into. Then fill it with clean cool water. Keeping the water changed out in your vase will prolong dahlia vase life because bacteria is the enemy of long lasting flowers.
5. Flower food- Dahlias are a bloom that likes food! They are hungry in the field and in the vase. Flower food (the stuff that comes in the packets) works wonders on prolonging your vase life. I notice a difference of usually 2 days when I don’t use it. Flower food contains a sugar that the plants feed on and it helps the bloom to stay healthy longer. It also contains a bactericide that will keep your vase water cleaner.
For commercial growers, I recommend a holding solution (I use Chrysal 2.0- holding/transport solution). This feeds the bloom but also helps to keep it in the state that you harvested. I recommend my florist customers to change over to flower food when I deliver since they are usually using them immediately. However if you want to hold a dahlia longer, use holding solution. It slows down the senescence of a flower.
6. Last but definitely not least- Cool your blooms. At a bare minimum let your blooms rest in a dark cool room for a few hours before using. If you have spare space in your fridge, place your vase inside. Do make sure you don’t have any open veggies/fruits giving off ethylene gas in your fridge. If you are a commercial growers, dahlias are the number one reason you need a cooler. Cooling dahlias makes a 2 day difference in vase life on average. Especially when it’s hot out. Cut your blooms, let them dry and place in a cooler for at least 12 hours. This will condition them well so that they hold up for your customer. A fridge will work for a home gardener. Temperature range for cooling dahlias is 38-42.
All of this can seem like a lot. After a while it become second nature but if you only have the bandwidth for a few things start with using flower food (you can find tubs of it online) and also cool your blooms— these will make the biggest difference!
