Brian answers readers’ horticultural questions
Q:I need to buy a heater to keep the frost out of the greenhouse on my allotment. The gardener just inside the site uses a little round heater in his greenhouse and assures me it keeps the greenhouse frost free. I am not convinced.
A: Have a careful look at your garden centre and you will find a heater which has a blue flame which runs on paraffin. The one-inch burner uses two gallons of paraffin in one week but is very economic. If you insulate the greenhouse with bubbled polythene this will keep the greenhouse warmer.
Q: My mum is going to come to live with me. She has always been a keen gardener and wonders if it would be possible to move her snowdrops into my garden. When is the best time? DK, Hilsea.
A: Snowdrops can be moved even if they are in full flower. I am really pleased you wrote to me because as well as your mum looking forward to living with you she will also see her snowdrops flower every February.
Q: We have moved to Purbrook and our neighbour tells me the huge plant on our fence is a passion flower. There are thick branches with masses of what I would call trailers. How and when can we prune it? H and PR, Purbrook.
A: Leave those thick branches, but all the trailing branches can be cut back really hard right now. Make sure you leave two buds on every trailer. Flowers will appear on all the new trailing branches next July.
Q: Every year we sow seeds in our greenhouse and as soon as the seedlings are ready to be pricked out we find the roots are being eaten by a white insect which is a bit thicker than a piece of cotton thread. Any idea what this is and how to kill it? I can’t find an insecticide which can be used to treat this. Amy, Sandown.
A: This is caused by a tiny fly which lays eggs in the compost and they hatch into these minute transparent worms. They are Scarid fly larvae. I have sent you details of where to buy a mains operated sulphur vaporizer. If you are online go to twowests.co.uk. Expensive but it will work. This device also kills red spider mite, helps prevent damping off in seedlings and also controls mildew on plants in greenhouses without damaging the plants.
JOBS FOR THE WEEK
There’s still time to plant shallots. Push the bulbs into raked soil. Plant bulbs about 10 inches apart with two feet between rows.
Seed potatoes are selling like hot cakes. If you are going to grow vegetables for the first time, don’t use potatoes bought in supermarkets. You need seed potatoes which will be virus free. You can get them from your garden centre.
Prick over the ground where spring cabbages are growing and give each plant only six pellets of Nitro Chalk each. This will induce growth and helps prevent bolting.
Brussels sprouts which have ‘blown’ (opened up like baby cabbages) can be eaten. Too many gardeners throw them away but they are even more tasty than spring greens and they don’t cause wind.
Buy seeds of perfumed, exhibition sweet pea seeds. These can be sown in a cold greenhouse or on a windowsill from now until mid-March.
If grass cutting is necessary, do it three days after the last rain so the surface has had time to dry out a little. Before mowing, drag a yard broom behind you as you walk over the lawn and cut the grass an hour later. Start the mower and any other garden machinery to check it’s OK, This will ensure it will start when you need it to in a few weeks time.
Got a question for Brian? Write to him at firstname.lastname@example.org.