It’s August and your Dahlia are all in full bloom. Here are some tips to help keep those babies blossoming for the rest of the season.
Watering
Once established, Dahlias benefit from a deep watering once or twice a week, instead of just slight frequent watering. If they need more you’ll know when the leaves starts looking limp. Plants should be watered from the bottom to the top. Watering the foliage and flowers could encourage earwigs.
***Dahlia confession time: Since I do take pictures of my Dahlia’s. I confess that I do sometimes water my flowers, just to take a picture. I also do it on a sunny day because I love to see the sunlight reflect off the water on the petals.
AND!!! Another reason I do it is because our pollinators stop for a drink as they collect their nectar
As with any plants, you should refrain from watering your Dahlia in extreme heat. The change in temperature from the heat of the sun to cold water could have an adverse effect on your plant. Your plants should be watered early in the morning or the evening time.
For containers: Once the stalk extends above the rim of the pot, water thoroughly. Never leave soggy!!! Under normal conditions water up to three times a week. In dryer conditions, you may have to water daily.
Staking
Giant Dahlias require staking. The combination of the height of the plant and weight of the flowers tend to make the plant top heavy. This can lead the plant to be a victim of any strong wind.
Some prefer to pinch their Dahlias as this promotes a shorter more compact bush.
I like to keep the giant in giant Dahlia, so I let them grow tall. This means
they will have to be staked.
There are other options to support the beauties. Options include the upside down tomato cage or just regular stakes. These stakes can be metallic, wood or bamboo.
The main rule of staking is to ensure stakes are strong enough to support the plant.
It is suggested that you stake your Dahlias at planting time. This is recommended because there is less chance of damaging the tubers. If however, you start your Dahlias indoors like I do, space wise this may not a favorable option.
I stake my Dahlia when I actually put them in the ground. Yes, there is a possibility of damaging the tubers but aside from their sensitivity to too much moisture; these little babies are very resilient.
When placing your stake, simply use those two God given visual aids in your head.
Insert stake as close to the stalk as possible without threat of damaging the stalk. Secure the stalk to the stake
Ensure the stalk is not attached to tightly. It should have a little bit of wiggle room as it will grow.
I have two words for you “pipe cleaners”, not just for cleaning pipes! This is what I use to secure my Dahlias to my stake. They are soft, so there is less chance of damaging the stalk and they are long enough that you can secure a branch further away from the stake. My color of choice is of course, is green. It blends in perfectly with the foliage.
Fertilizer
Dahlias require a fertilizer low in Nitrogen, too much Nitrogen will give you lovely foliage but not many flowers. e.g.: 5-10-10 or as close as you can find.
Apply 30 days after planting and monthly. The three numbers signify the nutrients Nitrogen-Phosphorus-Potassium (N-P-K). The numbers represents the percentage of each nutrient in the fertilizer. Do not over feed.
N – Nitrogen encourages the production of chlorophyll; each application of nitrogen encourages a taller, greener plant.
P – Phosphorus aids in root development and encourages flowering and increases bloom size
K – Potassium guards the plant against diseases, protects against drought and cold tolerance.
For Containers: Fertilize once every two weeks from June through September with a low nitrogen fertilizer.
Fungus
Excess moisture and bad air flow can cause Dahlias to develop mildew and/or other types of fungi. You can spray your Dahlia with store bought fungicide or make you own.
Improved air circulation will also benefit your Dahlias. Simply trimming the lower leaves on your plant will improve air flow. Better air flow, less moisture, less chance of mildew on the plant.
Pests – ohhh!!! How they bug me (get it!!!) These beauties are not just loved by us, they are also loved by Earwigs, Cutworms, Slugs, Corn root worm to name a few.
Many options are available from your gardening center for controlling these pests
There are many options for slug bates out there. A cup a Joe, Miss Diva? Coffee can be used as an effective repellant for slugs. Simple soak around affected area. Once the Dahlias have reached full height, this is no longer necessary
Deadhead
Deadheading, simply means removing all spent flowers.
Removing the dead flowers makes your plant look healthier. The biggest benefit of deadheading, it ensures continuous flowers production until the first frost. You may just have to invest in a few extra vases to hold these beauties.
Cleaning off the dead flowers also makes you plant and by extension your garden look that much better.
*** When deadheading, there is often some confusion between new buds and those that should be removed. Distinguishing
between the two is actually quite simple.
Since deadheading your plants provides so many flowers. We’ll need to know
how to make them last longer once they’re cut and brought inside.
Once you cut the flowers, run hot water over the cut ends. This helps to seal in
moisture which in turns prolongs the life of the cut flowers.
Disbudding
Dahlias buds grow in groups of threes, the central bud and two lateral buds. Remove
the two smallest buds, this sends all energy to the remaining bud.
***Disbudding will produce larger (but fewer) flowers. This is a common practice for flowers used for show.
I don’t usually disbud my entire dahlia plant. I love the flowers at any size but I do a few branches, just to get a few bigger ones (so I can go ooohhhh aaahhhhh!!!!).
I do pay closer attention to my dinner plates. The size and weight of one of these glorious blooms, can be too much for the branch. Disbudding reduces the weight on the branch and provides more room for the flower to grow. Of course because there is only the one flower, you will be rewarded with a larger one than if you left all three buds..
Pinching
Pinching promotes a compact, bushy plant with a lot more flowers. For the large
dinner plates dahlias pinch out the center growing tip right above the 3rd full
sets of leaves. For an even more compact plant, pinch at the 2nd full set of leaves.
So tell me Who’s Your Dahlia?