Eric Robson and the team are in Newcastleton in Scotland for the final GQT of 2012. Bob Flowerdew, Matt Biggs and Anne Swithinbank join Eric as this week's GQT panel.
Produced by Howard Shannon
A Somethin' Else Production for BBC Radio 4.
Overflow and notes:
Q. I have a north-facing concrete garden, in the constant shade of my house. What can an armchair gardener do with this garden?
A. Get a greenhouse and also consider building some raised beds from railway sleepers. Small trees could be planted in large containers, and walkways covered in bark or gravel to hide the rest of the concrete pad.
Q. When and how hard should a Hydrangea Hortensia be pruned to encourage it back to life after being cut down to ground level?
A. Leave the thicket of stems that have grown back until they are ready to flower, then after flowering some of the stems can be thinned out. Leave the flower heads on the plant to protect developing buds below.
Q. What is the best way to move my clump of Common Dog Violets from a gravel bed when I undertake re-landscaping next spring?
A. Divide the clump into smaller pieces in the spring and replant into trays of potting compost before planting out again into multiple clumps.
Q. How does the panel recommend making the most of cold frames attached to a greenhouse?
A. Cold frames are good for over-wintering almost-hardy plants that will overheat in the greenhouse. Potted-out Strawberry plants can be kept in the cold frame and insulated space blankets can be laid over the frames to keep Fuschias and Pelargoniums through the winter. Seeds that need a cold period, such as some trees, shubs and herbaceous plants, can be put in a cold frame to break their dormancy.
Q. How do I look after my large Mock Orange (Philadelphus) bush? Last year I pruned them and this year they did not blossom.
A. These should be pruned directly after flowering but will not respond well to being shaped in general. To reduce the plant in size whilst maintaining its flowering, thin out the shoots annually. Philadelphus Microcarpam is a recommended smaller variety of Philadelphus.
Q. Against the odds a vine has survived after the destruction of its greenhouse home. How can we encourage it to fruit?
A. Prune back very hard to remove last year's growth. Leave two or three shoots on each shoot and remove again any shoots that do not develop flower trusses on them. When berries develop, remove intermittent bunches to encourage the vine to ripen sooner and shorten the shoots again to concentrate growth.
Q. Would Myrtle grow in the Scottish Borders?
A. Temperatures below -8 or -9 degrees will harm a Myrtle. They can be grown in a conservatory or greenhouse, or in pots that you can move inside in the winter.
Q. Will a tree grown from a plum stone bear fruit and if so, when? It is currently about 18in tall.
A. This needs to be planted out, as plums are not happy in pots. It probably will bear fruit, though in its original form.
Q. How do you garden when you only get 7 hours of sunshine in the whole month of July?
A. Jerusalem Artichokes, Celeriac, runner beans and even roses did OK this year despite the wet weather. A greenhouse will make your life easier as a gardener, as will a helmet with a torch on top!
name: Howard Shannon
Produced by Howard Shannon
A Somethin' Else production for BBC Radio 4.