I have grown up in a family of rhubarb fanatics! The sweet taste in pies, jams, and cakes is just the way to wake your body up after a long, dark winter. Recently, the rhubarb that I have growing has been flowering very frequently. I can go out a pull seed heads off of nearly every plant and it has always puzzled me (as well as frustrated me to no end). I have also had many friends post pictures on social media of their rhubarb going to seed asking “What is this crazy thing!?” It is my goal in this blog post to share why rhubarb goes to seed and what you can do about the flowers on your rhubarb.
Flowering rhubarb can also be referred to as “bolting” or “going to seed”. Gardening Know How mentions different factors that can affect how often rhubarb goes to seed. First, the variety can be a determinant. When comparing heirloom varieties and modern cultivars, heirlooms flower much more. Next, the plant must be mature in order to flower. The older the plant is, the more it goes to seed. This, along with heat, is the biggest reason that I assume my own rhubarb has been flowering so frequently this summer. Rhubarb grows better in nice,
cool temperatures. This month has been exceptionally warm for the area I call home which I assume is leading to more flowers on my rhubarb. Lastly, stress, which can be brought on by a lack of water and nutrients, animals digging, and pests, can lead to flowering rhubarb.
When rhubarb goes to seed, the energy that would be used to produce leaves goes to the flowers. I have found that when my rhubarb has lots of seed heads, the growth of the plant is stunted until they are removed. The plant can still be eaten and there is nothing wrong with harvesting it. Rhubarb-Central.com recommends removing the flowers or seedpods as quickly as possible in order to ensure that you harvest high quality rhubarb with the greatest yield. An article from Montana State University (MSU) states that letting flowering stalks form completely will take away nutrients from the petioles, the edible stalks, and roots and transfer it to the seedpods. You can simply prune away the flowers whenever you see them appear.
There is no way to rid your rhubarb of flowers, but there are many ways to prevent it. First, you can try different varieties to test which you like the most. As mentioned, rhubarb grows best is cool temperatures, so having it in a shaded area or planning ahead and putting mulch around the base of the rhubarb before a hot period of time and keeping it nice and moist can prevent heat playing a role in bolting. Similarly, reducing the possibilities of stressors by watering frequently, fertilizing, and keeping your pets out of your rhubarb will help. MSU recommends planting rhubarb in well-drained, slightly acidic soil with a lot of organic matter and fertilizing just as the stalks first appear with something like 16-16-16. Also, breaking rhubarb up into smaller clumps will, in a way, “reboot” it and you won’t have to deal with seedpods for a few years. Monitoring your rhubarb closely for pods and removing them will not rid of them forever, but it will ensure that you are harvesting the best rhubarb.
In conclusion, there is no way to completely rid your rhubarb plants of bolting or going to seed, there are ways to prevent it. Keeping a good eye on it and spending some time removing seed heads if you have any will pay off by providing you with delicious, high quality rhubarb. So get on your gardening gloves and get out there to pick some rhubarb! And please share your favorite rhubarb recipe. I am always looking for new ones! Here is my family’s favorite that we make nearly every week in the summer.
My Great-Great-Grandma’s Rhubarb Cake
1 ½ c. brown sugar
½ c. butter
1 c. buttermilk
2 c. flour
1 tsp. vanilla
1 tsp. baking soda
½ tsp. salt
2 c. rhubarb cut into ½” chunks (I always use a cup or two more)
¼ c. sugar
1 tsp. cinnamon
Cream brown sugar, softened butter and egg in a mixer bowl. Add buttermilk and mix. Then add flour, vanilla, baking soda and salt. Mix thoroughly. Finally, fold in rhubarb. Pour batter into greased 9×13-inch pan. Combine ¼ cup sugar and cinnamon; sprinkle over top of batter. Bake at 350 degrees for 45 minutes. Top with whipped topping.
- Use fresh rhubarb in summer or, for a winter treat, use frozen rhubarb as a reminder of warmer times!
- If buttermilk is not available, use 1 cup milk with one of the following: 1 tablespoon vinegar or 1 tablespoon lemon juice or 1 ¾ teaspoons cream of tartar.
MSU-Bozeman News Service. (2002, July). Doctor Bob’s northern gardening tips: rhubarb growers: ban the boom!. Montana State University. Retrieved from http://www.montana.edu/news/415/doctor-bob-s-northern-gardening-tips-rhubarb-growers-ban-the-bloom
Rhoades, H. (2015, January). Rhubarb flowers: what to do when rhubarb goes to seed. Gardening Know How. Retrieved from http://www.gardeningknowhow.com/edible/vegetables/rhubarb/rhubarb-bolting.htm
Rhubarb-Central.com. (n.d.) Rhubarb flowers or seedpods: what to do with the rhubarb flower stalk or seedpod growing in the rhubarb. Retrieved from http://www.rhubarb-central.com/rhubarb-flowers.html