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Eric Robson hosts the horticultural panel programme from Cornwall. Chris Beardshaw, Anne Swithinbank and Matthew Wilson answer questions from the audience.

Eric Robson hosts the horticultural panel programme from Cornwall.

Chris Beardshaw, Anne Swithinbank, and Matthew Wilson answer questions from the audience.

This week the panel discuss how and when to cut back lilacs, how best to cultivate a lime tree, and how to create a 'tropical jungle' in a UK garden. They also reveal their topical tips for this time of year.

Matt Biggs investigates the fascinating story of the inspirational plant hunter William Lobb, and Matthew Wilson takes a trip round the Lost Gardens of Heligan.

A Somethin' Else production for ´óÏó´«Ã½ Radio 4.

Available now

43 minutes

Last on

Sun 8 Nov 2015 14:00

Thunderbox

Thunderbox
Signatures of the Helligan outdoor staff who left for WWI can still be seen on the wall of the gardeners’ lavatory

Questions and Answers

Q – Why has my Hibiscus stopped flowering after several years?Ìý I’ve had it for eigth years, it’s in acid soil and full sun.Ìý I also use chicken manure.

Panel (in unison) – Don’t use chicken manure!

Anne – It’s having too good a time; stop feeding it.

Matthew – Hibiscus do quite well in pots – they respond well to being strangled – so you might want to try that


Q – Could the panel advise on the correct techniques and timings for pruning overgrown Lilac trees.Ìý They’re in the front garden and are about 15-20ft (4.5m-6m) tall with lots of suckers.

Chris – Tackle these when you’re feeling ambitious! We’re talking about Syringa vulgaris – the broad-leaf, vigorous Lilac.Ìý Don’t worry about over-pruning them; if they are mature plants you can’t really.Ìý Cut it back about two-thirds of its total height and then select the suckers that you then want to allow to prosper.Ìý You will lose flowering for a short period but they will come back into flower.

I think you can prune at any time.


Q – I have a Salvia ‘Hot Lips’ – this year the flowers are mainly white – how can I get the red/white flowers back?

Matthew – The Salvia ‘Hot Lips’ does this.Ìý It’s quite weather dependent.Ìý Also, the longer they are in the ground they run out of steam – so you might want to add a bit of general purpose fertiliser.Ìý Prune in late spring.

Ìý

Q – I have a very vigorous Kiwi.Ìý It is eight-years-old – when can I expect my first flower and my first fruit?

Matthew – Kiwis like to be in pairs so it may never give you the goods if you’ve only got one.

Anne – You should prune it to encourage it to flower.Ìý There is one called ‘Jenny’ that is self-fertilising if you only want one.Ìý

Chris – Think of it as a vine or a vitis – if you can grow grapes then you can grow Actinidia (Kiwis).Ìý So give it a nice sunny wall, protect it from cold winds, and train it up 6-8ft (1.8m-2.4m) on a single stem and then go horizontally.Ìý There is one called ‘Solo’ that is self-fertilising and will fertilise others which could be good.

Ìý

Q – I’m replacing an old shed with a summer house and I’d like to make the area around it into a tropical glade.Ìý What plants can you recommend that are hardy but will give the feel of a tropical jungle?

Anne – Clerodendrum bungei because it looks very tropical.Ìý Also, iris confusa – the ‘Bamboo iris’.Ìý And Persicaria ‘Red Dragon’.

Matthew – I would go for Hydrangea ‘Villosa’ – it’s a hydrangea on steroids!Ìý Also, Eupatorium purpureum or ‘Joe Pye’ weed.Ìý Thalictrum ‘Elin’ – big bamboo-like plant.

Chris – Musa basjoo – the ‘Hardy Banana’.Ìý A must have is Tetrapanax papyrifer – huge palm-like foliage and a very delicate leaf.Ìý Cannas of course, start them off about Boxing Day, say, with lots of organic matter and they’ll flower in April/May.Ìý

Ìý

Q – I don’t use sprays on my fruit or vegetables; how do I prevent my ‘Williams Pears’ from developing acne spots?Ìý They are delicious but look terrible.

Chris – It could be difficult without sprays.Ìý Once it defoliates you need to take all the foliage away and then burn it rather than composting it.Ìý You need to completely clean the plant in this way.Ìý You will need to hope for good weather conditions too.Ìý A dry spring will really help.Ìý

Anne – Generally improving the health of the plant helps.Ìý Dig out a planting hole and mulch around the base.Ìý

Matthew – Taking the grass away and mulching will help to seal the spores in the ground.

Ìý

Topical tips

Matthew – Deep clean your glass house – perfect time of year to take everything out and wash the inside thoroughly

Anne – Sowing broad beans and hardy peas – ‘Aquadulce Claudia’ or the ‘Valenciana’ for the broad beans. Make a double row, about a foot (30cm) apart, and set the seeds about 6 inches (15cm) apart from each other.Ìý The beans want to be about 2 inches (5cm) before Christmas.

Chris – Start protecting your plants from the wind – go out with a pair of loppers and prune down your shrubs to stop wind rock

Ìý

Q – Is there anything that you would never, ever grow again?!

Chris – Dracunculus vulgaris – The Devil’s Lily or Dragon Arum… it emits a rotting meat smell and stinks the house out!

Broadcasts

  • Fri 6 Nov 2015 15:00
  • Sun 8 Nov 2015 14:00

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