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Peter Gibbs and his panel make a return visit to the John Innes Centre in Norwich.

Peter Gibbs and his panel make a return visit to the John Innes Centre in Norwich. Bob Flowerdew, Christine Walkden and Matthew Wilson anser the audience questions.

The panellists discuss maggoty plums, the best approach to pruning blackcurrants and how a greater understanding of pesticides might help amateur growers to reduce their use in the horticultural industry.

Peter Gibbs examines some of the 3500 varieties of peas on offer at the John Innes Centre, discovering how this vast collection is being used to inform and ensure the future of pea growing internationally.

Produced by Darby Dorras
Assistant Producer: Hester Cant

A Somethin' Else production for BBC Radio 4

Available now

43 minutes

Fact Sheet


Q1 – I study the development of the carnivorous traps of plants called specifically Utricularia Gibba (floating bladderwort). What is the panel’s favourite modified leaf?


Christine – I like Sarracenia – long tubes with fascinating stories associated with them.


Bob – the asparagus shoot – I don’t think anything can beat that.


Matthew – I am very fond of Colletia Paradoxa (The Anchor Plant). It is a wonderfully structurally exotic plant.


Q2 – What is the best way to prune blackcurrants?


Bob – Blackcurrants fruit on the wood that grew last year, and that is growing on the wood than grew the year before. You need to cut out some of the oldest branches from near the base leaving more space. Leave the youngest strongest branches. Do this just before you pick the fruit. 


Q3 – Can you recommend a small tree or large shrub to compliment my contemporary cedar clad house? I am also near the A11 so I have some noise to mask.


Matthew – Get a small water-feature to create a noise in the foreground, like a brimming pond which will distract the ear from traffic in the background. Get something multi-stemmed for the tree like Malus Toringo (Crab Apple).  For something evergreen go for Pinus Radiata (Monterey pine) or Pinus Mugo (Dwarf mountain pine).


Christine – I would be looking at the Griselinia and also some of the Escallonia’s


Bob – I would go for a Columnar Yew but the yellow ones and get a group of 3 of them.


Q4 – How can I encourage my Sorbus Vilmorinii (Vilmorin Rowan) to set berries?


Bob – If it is producing flowers that is the important bit as it is actually willing to do it. Check for water-stress, if it hasn’t got enough moisture then that’ll be the issue. And shortage of potash, plants need potash to flower and fruit.


Q5 -  I want small trees for my wedding decoration – if I plant them in pots this autumn will they be ok for June? And which variety is best?


Bob – I can give you a very special one – just north of Wymondham is an oak tree on the side of the road called Kett’s Oak and my ancestors were involved with a local rebellion and the tree is still there. You can pick the acorns which will be falling about now and by June you will have a small sapling.


Christine – One option is to get hold of things called whips which are generally single stemmed plants around 3 foot (0.9m) high which you then develop into a standard tree.


Matthew – you could get bare root trees in autumn which would be a lot cheaper and pot them into the right size and style you like but you won’t get a lot of growth on them, so buy them at the size you want them to be.


Q6 – I have two Salvias (love and wishes) growing in pots – I have been told they need winter protection. Shall I cut them back before I put them into their winter sleep and when is the best time to propagate these plants?


Christine – Give them more protection, put them under glass and fleece the plant as well. Now would be the time to take cuttings and pot them on in the spring.


Q7 – How do I stop getting maggots in my plums?


Bob – Watch the tree carefully – it is usually the first ones which start to ripen which have them, so take them off and bury them and the main crop should be alright.


Q8 – Can you solve a debate between my partner and I – we have an allotment under a huge oak tree on a slope and a long walk from a water tank. Should we keep it or is it time to move on?


Christine – Keep it! Enrich the soil and get some advice from other owners on what grows well in that area. Just enjoy it and grow it.


Matthew – Don’t cultivate the whole thing in one go but don’t give up on it.




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