Now that the dahlias are blooming I have to wonder why I didn’t plant dahlias in a few more different varieties. Every spring when all chance of frost is gone, I plant a sampling of dahlias that are new to me. There are so many choices it’s almost crazy, over 20,000 cultivars, but I decide on a few large bloomers and one or two smaller varieties.
The great thing about planting dahlias is that the more flowers you pick to bring indoors, the more they flower. If you don’t intend to pick flowers for vases then you must regularly de-head the spent blooms or else they will go to seed and stop flowering. As well, you can count on the dahlias to bloom right through into the fall. If you want to keep and store the dahlia tubers for next year’s garden you must lift the tubers before frost. I’m rather lazy that way and I just leave them in the ground to rot and add organic matter to my soil. Part of the fun for me in growing dahlias is to try different cultivars each year.
The color spectrum of dahlias is very wide, and many are in the dark deep hues. Colors range from white to red, orange to yellow, and pink to purple in various patterns. Dahlias are grouped according to the structure of their flower. Each group then has small, medium and large flowered cultivars. The giants or dinner plate sized dahlias are quite spectacular, perhaps almost over the top. Some are rather flat petaled and others are finely cut and called cactus. there are ball dahlias where the the flower heads are ball shaped. Giant dahlias can have blooms over 10 inches in diameter, while mignon dahlias are only 2 inches in diameter. Their blooms may be single or double.
You can purchase dahlia tubers from your garden center or through mail order nurseries. When frost free nights start plant dahlia tubers directly into good nutrient rich garden soil in the sun. Plan to water and fertilize your dahlias regularly. The larger ones will need staking to hold up their top heavy blooms. Fertilize with fish, blood or bone meal 1 week after planting. From mid summer on feed them once a week with a fertilizer high in nitrogen and potash. Keep them well watered.
If you decide to conserve your dahlias for next season, cut the stem down to 6 inches above the ground after the leaves have been blackened by frost. Dig up the tubers, knock off any excess soil but do not clean with water or the hose. Get them wet now and you will have mold by mid winter.
Label each tuber with it’s cultivar name, and let them dry for a couple of weeks. Dust the tubers with yellow sulphur to prevent mold and mildew and pack them into a box with peat or dry sand. Store in a cool frost free environment until spring when the cycle begins all over again.