Rhubarb talk
Rhubarb is often a maltreated vegetable (it is technically a vegetable, although I usually consider anything that can be eaten with custard a fruit) consigned by many gardeners to an odd corner where little else will grow. I must confess to being a rhubarb abuser, with both of my patches in fairly inhospitable areas. However, rhubarb is a remarkably tolerant plant. It’ll survive almost anywhere producing crops year after year if given an annual feed of manure or rich compost and a ‘recharge’ every four to five years. Manure and compost can be applied as mulch around plants, technically known as ‘crowns’ any time in winter. ‘Recharging’ however, while also a winter job, is best done before the end of January in my opinion.
Rhubarb, as horticultural speak puts it, is ‘propagated by division’ (it can also be propagated by seed but it’s a lengthy process). Translated, this means new plants can be produced by digging up established crowns, chopping them into several bits and replanting the best pieces. A spade is the instrument for this act of seeming savagery. The first step is to carefully excavate a mature clump, no mean feat as the rhizomes (thickened roots) penetrate deeper than might be expected. Once extracted the clump needs to be sliced into portions each having a good piece of rhizome and at least one clearly visible surface growing point or bud. Again, it is usually possible to perform the butchery with a spade but an old saw is an alternative. As when dividing any perennial plant, the younger growth on the outside of the clump should be favoured for replanting. This is likely to reshoot more vigorously than the older centre which is best discarded.
A good sized dug up clump can usually be split into three or four viable portions or offshoots. These should be planted without delay. Do not believe the old gardening lore that leaving newly divided rhubarb offshoots on the surface for weeks will somehow give them extra vigour. Planting can either be on a new site or the same ground; rhubarb doesn’t seem to suffer from replant diseases. Only set out one offshoot per planting position. Working some manure or compost into the area will help get the new plants off to a good start. Apart from this nothing else should be needed other than occasional watering if the spring or early summer is dry. Do not, though, risk retarding rejuvenation by pulling stalks in the first year after planting. New crowns need a period of convalescence after the shock of surgery. It is only in the second year, by which time there should be strong new growth, that harvesting can begin. Even then go easy; it can take two years for recharged crowns to reach maximum productivity.
If you have a lot of rhubarb plants that need recharging, with three or four viable offshoots possible from each clump, there is the question of what to do with them all. Even rhubarb connoisseurs will not want a plantation. One option is to consider using some of the offshoots for ‘forcing’. This is how the pale pink stalked rhubarb seen for sale in late winter and early spring is produced. And you don’t need the forcing sheds, heating and other paraphernalia employed in Yorkshire’s famous ‘rhubarb triangle’ to make this work. Here are two good examples; firstly via the Slowfood organisation and secondly on Wikipedia.
The no fuss method forcing rhubarb outdoors is simply to place a suitable container, for example an upturned dustbin, over an established rhubarb clump. However, while this’ll give pale stalks, it won’t produce them much earlier than those from plants left uncovered. Nor is it a foolproof process, rot often affecting the enclosed stalks. A better option is to take offshoots from an old clump that’s being divided and place them in a more cosseted environment, perhaps a shed or garage, or better still, a greenhouse or polytunnel warmed by winter sun. Rather than stuff the offshoots under a bucket or tub I place them in a metre cube crate. This is half filled with spent compost into which four to six offshoots are part buried. Thick black plastic sheeting is then spread over the top. This not only excludes light but, with the crate in a greenhouse, accentuates the warmth generated by any sunshine. I’ve used this method for several years now and usually get a forced crop of tender pale pink stalks at least four weeks before the outdoor ones are ready.
One final point to remember when growing rhubarb, especially if forced for the earliest possible cropping, is that some varieties start into growth much sooner than others. Many people wrongly assume rhubarb is just ‘rhubarb’. In fact there are several hundred varieties. The collection at Clumber Park in Nottinghamshire has 130. While few are now grown commercially, one that’s stood the test of time is Timperley Early. Its main virtue, as the name suggests, is that it is ‘early’, always the first to crop. It’s the variety I force every year as well as making up nearly half my 20 or so outdoor clumps. If you’re starting out with rhubarb it’s probably the best all-rounder. Fortunately crowns or pot grown plants are readily obtainable. A Web search will dig up dozens of suppliers.
We hope you enjoyed reading Mr Fluttergrub’s Rhubarb Talk. Maybe you have experience of growing rhubarb yourself? If so, we’d love to hear about it so we can share your knowledge on the WWOOF UK grapevine. Email us: editor@wwoof.org.uk
