Rhubarb is a delicious garden plant, and who doesn’t love a good rhubarb and strawberry pie? So if you’re growing rhubarb, and you notice it starting to flower, you might be wondering; does rhubarb die after flowering?
In this post, I’ll answer that question, as well as other common questions related to rhubarb flowering. Read on to learn more!
Rhubarb does not die after flowering. However, its production of edible stalks (petioles) will slow. Most gardeners agree that it is best to remove flowers and seed pods as soon as you see them.
What Causes Rhubarb to Flower?
When rhubarb flowers, it is called “bolting”. This can happen for a variety of reasons, and it’s important to understand those because some of them can be prevented.
First, certain types of rhubarb, like Victoria, MacDonald, and Red Crimson are much more likely to bolt often. Most other, more modern varieties have been bred to bolt less often, so they can be grown to crop over a longer period of time. Avoid buying these three varieties if you don’t want your rhubarb to flower often.
Many types of stress can also cause rhubarb to bolt. This includes not enough watering, being transplanted too suddenly, pests, lack of nutrients, animal damage, and more. Keep your rhubarb as happy and stress-free as possible.
Additionally, high temperatures can cause rhubarb to bolt. Rhubarb’s ideal temperature is below 40°F (4.5°C) in winter, above that in the spring, and average summer temperatures that don’t go above 75°F (24°C). So a good range for rhubarb, during the growing season, is 40-75°F (4.5-24°C). If it gets above that, it can cause rhubarb to bolt.
Lastly, the older a rhubarb plant is, the more likely it is to bolt. After a few years, rhubarb is much more likely to bolt. To prevent this, you can split the crown of your older rhubarb plants, effectively resetting the clock.
Splitting the Rhubarb Crown to Prevent Flowering
To split the rhubarb crown, start in early spring. Dig up the entire crown with its roots. Separate the crown into clumps, and make sure each rhubarb clump contains at least one bud and a good amount of roots. Then simply replant them as separate rhubarb plants.
Older rhubarb plants can be quite woody at the crown, so they may be difficult to cut through. Use a sharp knife or pair of garden shears, and make sure whatever garden tool you use is clean. It may require some effort, but don’t worry about damaging the rhubarb. As long as you only cut the rhubarb crown and not the stalks or leaves, the plant will be ok.
Should You Cut Flowers Off Rhubarb?
In short, yes, it’s a good idea to cut off the rhubarb flower stalk. Once rhubarb bolts, it will start putting more and more energy into those flower stalks, instead of the stalks (petioles). This means your edible rhubarb crop will be smaller and grow slower.
And because rhubarb can be propagated by splitting the crown, there’s really no need to let the plant go to seed. So you should cut off rhubarb flower stalks as soon as you notice them.
To remove flowers from rhubarb, get a sharp, clean knife or pair of garden shears. These stalks start as buds; if you see one of these, simply cut it off from the base. Once it grows into a flower stalk, do the same thing; cut as close to the base of the stalk as possible, removing the entire flower stalk.
The reason you want to remove the whole stalk is because if you leave part of it behind, it will start to rot. Then, pests and diseases are more likely to bother your rhubarb plants. So make sure you remove as much of the flower stalk as you can.
Should You Let Rhubarb Go to Seed?
Usually, there is no reason to let rhubarb go to seed for the same reasons above. You can propagate rhubarb by splitting the crown, so there’s no need for the seeds. And once rhubarb goes to seed, the petioles or stalks, the part you really care about, won’t grow as well or as quickly.
What Happens if You Let Rhubarb Flower?
When rhubarb flowers, it starts by producing small buds. These buds will turn into flowers with seed pods. They will grow very quickly. Once they are fully grown, the flowers and seeds will start to dry out and turn brown, followed quickly by the rest of the flower stalk. This is when rhubarb seeds are ready to be harvested.
Since these stalks are growing so quickly, they are taking a lot of energy from the rhubarb plant. You may notice rhubarb flower stalks get large very quickly, which is why it is important to remove them as soon as you notice them.
Because so much energy is being put into the flower stalks, the growth of the stalks (petioles) will slow. Eventually, it could stop completely. So the only part of your rhubarb that will be growing is the new flower stalks.
If you’re growing rhubarb to eat, then this isn’t helpful for you. You want as many petioles, or stalks, as you can get, and for them to grow as much as possible. So letting rhubarb flower would be counterproductive if your goal is to harvest rhubarb and make a delicious pie or jam.
So there is technically no harm in letting rhubarb flower, as the plant won’t die after it flowers. However, it is a bad idea if you want to grow your rhubarb for its yummy stalks, and not for seed. So it’s usually best to cut off rhubarb flowers as soon as you notice them.
Can You Eat Rhubarb When it Has Flowered?
Yes! The petioles, or stalks, of the rhubarb plant are still perfectly edible after it has bolted.
The flower stalks, though, like the leaves, aren’t edible. If you want to harvest your rhubarb for eating, you should remove these parts first, and then harvest the stalks. Some plants change flavors after flowering, but rhubarb is not one of them. So even if your rhubarb has bolted, it will still be just as delicious as you’re expecting.