大象传媒

Eric Robson chairs the horticultural panel programme in Stoke on Trent. Taking questions from a local gardening audience this week are Matt Biggs, Christine Walkden and Chris Beardshaw.

Produced by Howard Shannon
A Somethin' Else production for 大象传媒 Radio 4

This week's questions:

Q. Is it too late to plant potatoes?

A. Potatoes can be planted throughout the year, but to extend cropping plant in large containers or compost bags and keep in an area where they can be kept frost-free at the latter end of the season. Plant a succession of early potatoes through the spring, have a break at 'Blight time' and then begin again in mid-August.

Q. I have three young apple trees. The Jonagold and Cox's Orange Pippin are fine, but the James Grieve is always covered in greenfly at this time of year. Why might this be?

A. If the tree is sickly, the chances are it will be a struggle, especially when competing with two other healthy trees. It might be worth checking the roots for any signs of what might be causing the trouble, such as compacted soil or standing water. In order to tackle the greenfly, place a nesting box nearby, as natural predators such as Blue Tits might be encouraged to feed on the aphids. If all else fails, the tree may need to be removed altogether.

Q. Do tomato plants grow well and fruit hanging upside down? What would be the best variety for this?

A. A hanging basket variety such as Tumbler would be best.

Q. Which vegetables could be planted in a north-facing plot in partial shade?

A. Anything rapid growing such as the salad vegetables - lettuce, chard and spinach - are recommended. If kept wet, Wasabi is one of the few plants that will grow well in those conditions. Herbs such as Sweet Cicely are also suggested.

Q. Is it too late to hard prune a Choisya bush that was badly damaged by frost in the spring. Will it still make new growth from the base?

A. With evergreens such as Choisyas, it is best to prune when they are in their first growth. Any time before midsummer's day will be OK in a slow season such as this one. As a precaution, the shrub can be cut back in stages, reducing the total canopy by a third in size or removing a third of the stems each year. On a damaged bush such as this, keep pruning to a minimum - removing only parts which are damaged, dead, diseased or dying. Feed with general fertiliser and water well during the warm summer season.

Q. How can a wild flowering lawn be established on an existing area of grass which is in part shade and currently full of moss?

A. Take off the mowings and reduce the fertility of the soil significantly. Don't worry about the moss unless it is really rampageous, in which case introducing plugs may be easier than seeding down. Species such as Celandine and Ajuga will do well in shady, damp areas. Oxeye Daisies and Buttercups will spread over time from the existing grass if managed well. Sorrel and Violets could also be grown.

Q. Do Wisteria take time to get established, or is there something wrong if the plant has not flowered for three years?

A. A grafted Wisteria plant will grow quite quickly, but ones raised from seed can take from five to 10 years to start flowering. If the plant is growing well, prune it in July, taking the side shoots back to two buds' length. Try to prune in such a way to encourage one or two of the stems up. Turning the stems horizontally will change the hormone levels in the plant and may encourage it to flower. Wisteria are best when grown against a south-facing wall.

Q. Does the panel have any advice for growing Morning Glory (Ipomoea 'Heavenly Blue')? The seeds germinate well and grow strongly until being hardened off and put outside. Would it be better to grow them indoors?

A. Morning Glory likes to have its head in the sun and free-draining soils. The past few seasons have not been the right weather - warmth, particularly longevity of warmth, is the key for growing these plants. A cool glass house or a conservatory would be a good environment for this. However, if they become too warm indoors, they can be subject to attack from red spider mite.

Q. What can be planted in the gaps left by tropical plants killed off by the last three years' worth of bad weather?

A. Rhododendron 'Polar Bear' and 'Arctic Freeze' lettuce are suggested! Native plants throughout the garden will be much better suited to cope with the poor weather conditions.
Eric Robson chairs the horticultural panel programme in Stoke on Trent. Matt Biggs, Christine Walkden and Chris Beardshaw take questions from the local gardening audience.

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