Rhubarb problems

[fran]

Hi folks! Very early this spring (I think) or over the winter, I planted some bare-root rhubarb crowns from Homebase into a fairly deep and wide hole - clearing the couch grass, brambles etc., and incorporating compost - so that the crowns were just showing, in an open site. I started them off in a pot as ground wasn't ready, but they did have one or two leaves on them. Over the summer the leaves died down but have been replaced periodically by one or two extremely small leaves, which have also then died back. The soil also seems very dry, but I have watered now and again. I think it is too dry for them. It hardly seems to rain on my plot - in SE London, and I'm now wondering what to do. I have read contradictory things about how deep the crowns should be planted. Shall I cover them with some more soil and see how they grow come the Spring - or try some more in a different place? I also planted about three crowns much too close together. The crowns haven't rotted and the roots seem to be well anchored into the ground.

Advice welcome. (I thought you could hardly kill rhubarb and it grew like a weed. Obviously not. Does it do better in a slightly shaded site?)

[ginger ninger]

I have my rhubarb in a large bendy bucket in semi shade, it's in a mixture of well rotted horse poo and compost, this retains water but not too much, plus I can drag it into the sun if I want. This is only the second year I've had my crown's so I'm no expert on them. I haven't pulled any off my crown's while I've had it, but I will next year.

[bazzaboy]

oh dear, Fran, that doesn't sound quite right, they should have put on thick stalks and big leaves over the Summer... But it's good that they're still alive, I get the feeling from what you say that they're holding their breath and waiting for better times in two respects, basically food and water! If you think of the size and rate of growth of rhubarb it's no surprise that it's quite a heavy feeder (the old jokes about manure on your rhubarb and "oh I prefer custard on mine" are there for a reason) so I suspect basically you need to improve the soil so it has more nutrients and better water holding... plenty of composted manure (NOT fresh at this stage though fresh manure can serve another purpose once the rhubarb is established) gently eased around the patch/crowns and next Spring ensuring it's damp but not wet will hopefully do the trick. Best not to force or use the crop next year (sorry!) as it would probably appreciate getting firmly established - once established, as you suggest, it's pretty tough and reliable.

Your depth of planting sounds OK; as far as shade is concerned it will tolerate (even appreciate) some shade as it has a huge leaf span if midday sun is hot and conditions dry, but it likes some sun and wouldn't be very happy in permanent shade. b.

[grannymem]

I found your advice, Bazzaboy, really helpful as I have similar, although I don't think quite as drastic. problems to Fran.
I planted 2 or 3 crowns this year in different bita of the garden to find a place where rhubarb would be happy. Only 1 seems to be doing well but it's in the middle of my small veg. plot and I think it's going to become a problem b taking up too much space.
Do you think I can move it safely and if so, when should I do the deed?

By the way, I do LOVE these forums!!

[bazzaboy]

A fully-grown rhubarb crown in the middle of Summer, GM, will cover a circular area of about 4 feet diameter which, if my maths is right (pi-r-squared?), ends up needing something around an unbelievable 50 square feet in total – quite a chunk out of a small veggie patch! And you’ve got three? Well the good news is it will happily intertwine with itself so you can plant crowns about, say, 2 feet (60 cm) from one another; also although most leaves naturally grow prone, if it’s close to an obstacle such as a wall or tub those leaves will happily sit upright and reduce the total area required. I’ve never tried it but if space is limited this suggests you might be able to pen it in using, for example, those 12-18 inch ornamental dividers (Wilkos?) or other low barrier to restrict its tendency to sprawl. Best moved in the Depths of Winter (you have those in Truro?) either way when it’s cold and least active, say Jan or Feb – but mark their current places NOW with some firm stakes alongside (stress “alongside” rather than “through”, we’re dealing with rhubarb here not Dracula!) so you know exactly where they are as otherwise once this year’s foliage has disappeared you’ll run the risk of injuring them with a spade or fork when digging them up… If they’re fairly young they won’t need splitting so settle them in their new location just below the surface (no harm in moving any soil that sticks, don’t “clean” them), then water well (or “puddle in”) to help the roots settle and firm and perhaps protect the surface with some leaves or compost. Best not to force or crop the first year though if you’ve three crowns probably no-one’s going to report you to the Western Horticultural Authorities if you try a Summer 2010 taster as a reward for your efforts! Hope it all works. b.

[grannymem]

You're a star, B! Very many thanks

[Alison]

A fully-grown rhubarb crown in the middle of Summer, GM, will cover a circular area of about 4 feet diameter which, if my maths is right (pi-r-squared?), ends up needing something around an unbelievable 50 square feet in total – quite a chunk out of a small veggie patch!

School boy error! It's radius squared rather than diameter squared so 2 x 2 x pi ie 12.5 square foot - still quite a large area but not as bad as first thought

[Flummery]

You don't expect much from a rhubarb crown in its first season. Generally speaking, you are advised not to crop from it in the year in which you planted it, to allow it to build up its strength. I'd make sure it's kept watered in its first season, then next spring - a whacking load of manure or home-made garden compost will see it ok. If it only throws up a few stick next year, don't pick them all - leave a few to die down at the end of the year. Give it a chance and it will become a decent plant. You can't rush a good garden!

[bazzaboy]

oops, thanks Alison, you're absolutely right, the equation IS radius squared.... But the calculation is right it's my terminology that's wrong, calling the "radius" the "diameter", duh! The RADIUS from crown to tip of large leaf is about 4 feet (just been and measured it, fortunately neighbours get used to these strange antics....!) so assuming the plant will grow in all directions the diameter will actually be approaching 8 feet (and thus total area 50 square feet....). As you say, big anyway! I've got three crowns competing in an area which is about 45 square feet (9 x 5) and they overlap, spill on to the path and clamber up the wall... Schoolboy punishment... 500 lines (do they still do that?) "I must not confuse radius and diameter!" Thanks... b.

[Tam]

Rhubarb can stand fairly damp situations and was often planted close to walls where rising damp occurred - this apparently was beneficial to the building, as well as the rhubarb

[fran]

Thanks Bazza. Really useful! I'll let you all know what happens.

[Storming Norman]

Fran,

I can't be a million miles away from you. If it does not do well next year PM me and you can have some of mine. I have far too much now since I dug up my very old plant and replanted bits of it.

All the bits have really thrived - I can spare some for you if you need it.

[jaykay]

When I planted my rhubarb, I didn't pick too many sticks during the first summer. Once the leaves and stalks had died away at the end of the plant's first year I mulched around the crown with manure, and left it like that for the winter. The rhubarb grew furiously the following spring, and has been going strong since.

I think they are quite hungry plants though, and have read that rhubarb does well if planted next to the compost heat, because it benefits from the run-off of nutrients from the decomposing matter in the compost.

[WrexTheDragon]

You can never add too much well rotten manure, also helps against frost for it's first few years.