The bees are buzzing and the mosquitoes are biting, summer is finally here! To celebrate let’s chat about one of the most rewarding and easiest summer flower to grow: cosmos. There are so many varieties to choose from (and new ones debuting each year) that they are guaranteed to keep your interest. Plus, our bee friends love cosmos. If you’re looking for a flower to help the bees and bring them to your vegetable garden, cosmos fit the bill pretty well.
The Victorian language of flowers definition of cosmos is: orderly, modest, and love flower, to name a few. Cosmos are definitely a modest beauty, not quite as flashy as a dahlia but definitely earn their keep and are a lot less fussy. In other words, cosmos may not be the star of the show but they are amazing supporting actors! While my zinnia patch has become the buffet for caterpillar and earwigs the cosmos are flourishing, undisturbed. Most buggy creatures aren’t fans of nibbling cosmos, even in its most vulnerable stage as a seedling, they taste yucky to them. Bonus points, cosmos are also yucky to rabbits and deer (but we all know that if they’re hungry enough…).
With only 2,000 square feet of growing space for a flower to deserve an exclusive spot in our garden beds they make great cut flowers, which cosmos do. They also need to be prolific, which cosmos are. Cosmos highlight the beauty of local flowers, these guys won’t be spotted in a Trader Joe’s and are only available to florists who purchase them directly from a local farm or grow cosmos themselves. Cosmos don’t ship well and do not store. That means, they need to go from the field to your vase within a day. Their vase life is decent, when harvested at the correct stage, they can last for about five days. That may not sound great, but add in the other buds on the stem that will bloom, you can get a solid week from them. At their peak, I find myself harvesting twice a day!
Cosmos are cold tender… really cold tender. They are truly summer flowers, in our area, planting them out in May (even with protection and covering) is a real gamble. A gamble I lost at this year. Even until Mid-June, it was rough. I was able to cover them and only had some minor frost damage, but damage is damage and can be heartbreaking. Fortunately, they are pretty fast growers, taking about 75-90 days to mature. You can get a head start by starting them indoors a few weeks before planting out but direct sowing is easy and the seedlings grow more stout. These guys germinate pretty fast, making them even more rewarding! Nothing like seeing plant babies thrive. Cosmos like full sun, and like most flowers, well-draining soil. Cosmos don’t need as much fertilizing as some other flowers but definitely benefit from a weekly dose of foliar fish emulsion and kelp.
Sometimes it’s hard for growers to want to cut flowers off but with cosmos, the more you cut the more flowers they reward you with! So don’t get shy about harvesting them. The trick to getting the longest vase life of these is to harvest them at a swollen bud stage, where it’s just about to open but hasn’t yet. Once the cosmos have been pollinated, they don’t offer much of a vase life. Their purpose in life has been complete. The flowers that have opened and are past the optimal harvest stage, I leave for the hungry bees but go back and deadhead them later. The cosmos try their mightiest to set seed, once they do that they are done. This is why it is so wonderful and important to harvest/deadhead them to keep them blooming happily for you all summer long.
Our cosmos are just getting started! We are growing quite a variety of them (because we just can't say "no" to such a pretty flower.)
Hope you enjoyed this dose of floral bliss!