As I sit to write this, we are a couple days into the spring equinox. And although temperatures have decided to take another dip into the deep freeze for the last days of March, it does not stop the dreaming of warmer temperatures, soft grass, green leaves and of course the rebirth of life in the gardens and in nature. Life that comes on slowly at first but then within all but a few weeks will come on with such vigor that one can only look with amazement. Amazement that from the depths of the semi frozen earth, with the first slight warming of the soil, things like this underutilized perennial vegetable spring to life to come forth and produce the first spring flush of mineral and vitamin rich deliciousness. The epitome of eating seasonally.
Although there are a few perennial vegetables that a person can establish to accompany the spring foraging around my yard as I did in Wild food foraging of edible wild greens for supper, such as Good King Henry, Sorrel or Winter onions, none will come on or produce like this underutilized perennial vegetable. Namely, Rhubarb (Genus Rheum in the family Polygonaceae).
Is Rhubarb a vegetable?
A fruit is defined as “the sweet and fleshy product of a tree or other plant that contains seed” which means that although rhubarb is typically prepared much like fruits such as apples, pears and such, rhubarb does not fit within this definition. And so, botanically rhubarb is actually a vegetable.
However, as explained in this Barnes/Richardson Global Trade Law article 1947: The Great Rhubarb Controversy, “Barnes, Richardson & Colburn partner Joseph Schwartz argued before the Customs Court. At issue in C.J. Tower & Sons v. United States was the tariff classification of fresh rhubarb from Canada. Under the then applicable tariff, rhubarb was either subject to a 35% duty as fruits in their natural state (para. 752) or a 50% duty as vegetables in their natural state (para. 774).” As a result of this 1947 ruling, rhubarb was classified as a fruit for tariff purposes and has been grouped as such ever since despite it botanically being a vegetable.
History of rhubarb
Rhubarb originated in China and was used medicinally for many centuries. However, as explained in the History of Rhubarb by High Altitude Rhubarb in Colorado, USA, “The first documented uses in western civilization are 2100 years ago when rhubarb roots were an ingredient in numerous Greek and Roman medicines.”.
According to this article "Widespread consumption of rhubarb stalks began in Britain in the early 19th century with its popular adoption as an ingredient in desserts and wine making" and proceeded to increase in popularity in Britain and the USA. In Canada, “Early European traders brought rhubarb crowns with them. Then the plant was brought across Canada by Hudson’s Bay Company employees (who were 80% Indigenous) and cultivated in gardens for each fort and outpost. Homesteaders and pioneers also brought rhubarb crowns or seeds with them.” according to the BC Food History article Savory Rhubarb. This would be one explanation as to why every abandoned farm yard always has a rhubarb plant or two.
Although rhubarb gained in popularity prior to WWII, following the war the use of rhubarb waned to it's current British Columbia, Ontario and Nova Scotia commercial production of 1250 metric tonnes (1378 US Ton) in 2022, according to Statistics Canada. In the USA, rhubarb is primarily commercially grown in Washington, Oregon and Michigan, with 1200 acres in production according to Michigan State University.
Health benefits of rhubarb
For the majority of my life I thought there was only two varieties of rhubarb, green and red. What I didn't know until recently is that there is over 60 varieties of rhubarb but only a small handful of them are grown commercially or in the home garden. With the amount of seeds that are produced on each plant, hybridization can happen with every crop of seed. But with so many possibilities, it can be difficult to determine varieties because there is no dependable plant key to determine the variety. As stated in the article Rhubarb Varieties by High Altitude Rhubarb “It is very difficult to identify any variety with any confidence. We all do our best. However, you’re best advised to rely on the description of the varieties characteristics than on the name associated with it.”
But whether you grow the more common varieties such as Victoria, Canada Red or one of the other varieties mentioned in 13 of the best Rhubarb varieties, the one thing that remains consistent is their health benefits. Being rhubarb roots grow deep, they mine a lot of the vitamins and minerals that are typically out of reach for most plants. And with the long winter behind us, the rhubarb plant is great for replenishing those vitamins and minerals.
According to the American Institute of Cancer Research, “The edible part of the rhubarb plant — the stalk — contains anthocyanins, which yield its bright red color. Anthocyanins are a type of flavonoid found in foods such as berries, red onions, black beans, red grapes and black plums. They act as antioxidants in test tube studies, but in the human body, their protection seems more likely to come from their role in cancer-preventive cell signaling. ”. The article goes on to further state that “Rhubarb is also a great source of vitamin K1, which is important for blood clotting and bone health. A half cup of cooked rhubarb provides more than one-third of the recommended dietary intake of vitamin K1, along with two grams of fiber (which helps prevent colorectal cancer), some calcium and vitamin C.”. Sounds like all wins to me.
WebMD also speaks to the health benefits of this underutilized perennial vegetable in their article Health Benefits of Rhubarb where they state that “Rhubarb is an excellent source of vitamin K, which is an essential vitamin for bone health and blood clotting. The vitamin A in rhubarb may also help to fight free radicals that cause skin damage and premature aging, keeping your skin looking healthy and youthful. It’s also high in antioxidants, and many other important vitamins and minerals that provide a variety of health benefits.”. The other important vitamins and minerals contained in rhubarb are Calcium, Vitamin A, Vitamin C, Potassium, Folate, Manganese, Magnesium. For a more in depth look into the vitamin and mineral breakdown of rhubarb, be sure to check out the United States Department of Agriculture analysis of raw Rhubarb, last updated in 2018. Rhubarb truly is a treasure trove of health benefits.
But like most articles, the WebMD article Health Benefits of Rhubarb cautions against the use of the leaves because they contain oxalic acid, a naturally occurring substance that inhibits the uptake of vitamins and minerals. The article goes on to further state that “Rhubarb is high in calcium oxalate. While the substance is mainly in the leaves, it’s also found in the stalks. Too much calcium oxalate in your diet may lead to hyperoxaluria, which is the buildup of oxalate crystals in different organs. These crystals may also promote the formation of kidney stones and increase your risk of kidney failure.”.
Growing Rhubarb
Rhubarb is one of those plants that is very adaptable to many different growing conditions. It is hardy from zone 3 to zone 8, it will grow in a variety of soil types and a variety of light conditions. Although it can work in a flower bed, in an orchard, in the garden or just tucked into an unused corner of the yard, like most plants the more favorable the growing conditions the better it will do. Although it really does prefer full sun, I know of plants that have done well with dappled light and others that only get about 4 hours of light a day. And in all cases, the rhubarb still produces reasonably.
Rhubarb really does do the best in a moist well drained fertile soil. However, if the soil conditions are not the best, I would still plant it as the soil can be amended to make it more to rhubarb's liking. Rhubarb does not like having continual wet feet so if possible I would shy away from planting in wetter areas. And if your soil is heavy in clay, which can also attribute to wet feet, it can create problems with the plant going root bound within the planting hole of the plant. To help avoid the plants from going root bound, burying things like old rubber boots in the bottom of the hole for the roots to wrap around will decrease this from happening. In both instances, making a mound of good organic soil and planting your rhubarb in that mound with the crown of the plant approximately 2 inches (5cm) below the soil surface will greatly increase your success. Being that rhubarb roots mine minerals and vitamins, over time they will mine into the less than favorable soil and help develop the soil whilst pulling out what they need. Periodic topdressing with good organic compost will aid with this.
With proper conditions, rhubarb plants can survive for decades. In my zone 3 sandy loam food forest orchard garden, I have two green varieties that I brought here when I bought the place 32 years ago. I think they are a Victoria variety but being they just showed up in my previous house, they are more likely a hybrid variety that self started from seed. Although I put a couple rubber boots in the hole before planting, I have done nothing special to these plants save for the occasional top dressing with manure, removing the old stalks and leaves in the spring and watering it when I water the rest of the garden. Only once during those years do I recall having to really deep water it due to an extended drought. Although a mulch can help with weed control and water retention when the plants are newly planted or when starting from seeds, once the rhubarb plants are established the leaves shade the ground and aid with water retention and weed control. After all, there are many rhubarb plants that dot the landscape in old abandoned yard sites that receive no attention whatsoever and they do well. It really is an easy plant to grow.
Although it is possible to start rhubarb from gathered seed, the only true way to ensure variety purity is to dig out off shoots or split existing known varieties. But that said, seed bought from reputable seed companies is another affordable way to get multiple variety pure starts.
Regardless of whether you decide to grow a pure variety or just grow what you can get your hands on, after your plant gets established it should provide that early spring and summer bounty for many years and decades ahead. Just like my 32 year old plants are doing for me.
During the lifespan of your rhubarb plants, they will will try to send up seed heads throughout the summer season. The seed heads should not be allowed to remain as they will take energy from the plant. Removal of the seed heads is done by grasping the stem and pulling straight up, exactly the same as you harvest the stalks.
Harvesting Rhubarb
It is recommended to not harvest any of the stalks for the first year to give the plant an opportunity to establish itself and setup for longevity of the roots. But the following year, a small harvest could be done depending on how the plant looks. If it is vigorously growing I would not hesitate to do a small harvest but if it is struggling, I would not recommend doing a harvest.
In the spring when the sun warms the soil to above the required 40 F (4.4 C) temperature it needs for it's winter dormancy, the roots will shoot up the first stalks indicating that spring is here and the promise of a great spring and summer is before us. Once the stalks have reached a useable size in diameter and length the stalks can be harvested. To harvest, grasp the larger stalk close to the ground and firmly pull straight up and a bit to the side to detach the stalk from the root.
Continue to harvest the larger stalks making sure to leave the smaller stalks to grow and feed the roots. Each spot that a stalk is pulled off the root will heal and allow for more stalks to be grown from the crown. Although it is recommended by most, including Ohio State University in their article Growing Rhubarb in the Home Garden, to not harvest more than ⅓ of the plant, because I do my main harvest once a year, typically mid summer, I harvest all the larger stalks leaving about ⅓ of the stalks behind to feed the roots for the winter that lies ahead. Harvesting this way certainly presents a visible difference when compared to a plant that is not harvested.
It is not recommended to cut the stalk off of the crown as the left behind piece of stalk can cause an entry point for moisture and disease which may kill the crown.
Once the stalk has been harvested, the bottom of the stalk is removed with a knife.
Then, the leaf is removed and added to the compost pile or left as a mulch layer. It should not be fed to animals.
The delicious, healthy stalk of rhubarb is now ready to take into the house to be preserved.
The plants are then left to regrow and top up the reserves in the plants. Smaller harvests could be done into the fall as it really does come back quickly as this picture indicates one month after harvest.
Whether you harvest throughout the season or with one big harvest, it is crucial that when you notice the new stalks getting small that you quit harvesting so that the roots can gather energies for the dormancy period during the winter. When temperatures start to get colder the plants go into a dormancy, the stalks that are present become a blanket for the long winter ahead.
Preserving Rhubarb
Once the stalks have made it into the house it is now time to wash the stalks and cut it into desired lengths. Whether you wash first and then cut is up to you. But for me, I find that cutting the stalks into a sink of water to be washed to be more efficient.
Once all the stalks are cut and washed they are then drained and can be then made into your favorite jam, jelly, compote or rhubarb crisp. But rhubarb also freezes exceptionally well and so I put it raw into a plastic bag and put in the freezer to use and/or preserve when it is cooler and I have more time. I do like to freeze in large bags as I find there is less frost and the bags don't get lost in the freezer.
Final thoughts
Although there are non edible rhubarb plants (Chinese Rhubarb - Rheum palmatum) that can be used in landscaping a space, I would suggest that any one of the 60+ varieties could be also used in your landscaping or in your garden to provide interest and supply healthy, delicious food for your family. This underutilized perennial vegetable really does have a magnitude of uses. Whether that be eating it raw with a little salt or sugar; or, in sweet spreads such as jams and jellies; or in baked goods such as rhubarb crisps, rhubarb cakes, rhubarb pies; or, in breakfast dishes like a Rhubarb Breakfast Cake as made by Homesteading Family; or, used in juices and wines; or, used in chutney's and this sweet and savory Rhubarb Relish my Grandmother, and now I, make.
Regardless of how you use rhubarb, I hope you found this information to be useful and that you consider growing and using this underutilized, healthy vegetable in your home and garden. If you would like to see a video I put together of harvesting rhubarb on my new YouTube channel, please go on over and check it out by clicking on the title - Harvesting Rhubarb. Also, please consider joining the My Boreal Homestead Life community. By supplying your email address at the bottom of the page and hitting "sign up" or by clicking Join, you will ensure you get an email notification when I post new blogs to the My Boreal Homestead Life site.
Thank you for joining me on the front porch of My Boreal Homestead Life as we explore this Homegrown, Homestead life, In a Modern World.
Additional Resources
- Harvesting Rhubarb - My Boreal Homestead Life
- Growing Rhubarb in the Home Garden - Ohio State University
- How to Grow Rhubarb Plants: The Complete Guide - The Almanac
- High Altitude Rhubarb - web site
