In the garden this week: September 3, 2010

Magnolia Iolanthe is opening her flowers

Magnolia Iolanthe is opening her flowers

• Spring is here. The magnolias are fantastic right at the moment so take the time to get out to parks and gardens to admire them.

• If you use annuals for spring display, you will need to buy plants now and get them out to the garden. It is too late to do seeds for spring but you can start your summer annuals in trays or pots for planting out later. If you are planting baby plants, pinch out the flowers and any long growths to encourage bushiness. If your plant gets stressed soon after planting out, it will try to ensure its survival by skipping most of the flowering step and going straight to seed. You can discourage this by disbudding it because this forces more growth.

• Now is the time to prune luculias which can get very leggy if left entirely to their own devices. Try and find two leaf buds down the stems and prune back to these. As the plant flushes with spring growth, it leads to a bushier shape.

• Get around all your rhododendrons and vireyas as soon as possible to get dead out wood and to carry out any pruning required. This is one plant you prune now, not after flowering. You want to make the most of the plant’s spring flush. If you prune them after that growth flush, you will weaken the plant and make it more difficult for it recover from heavy pruning. Follow up with a feed and some mulch – rhododendrons are surface rooting so they can easily fry in dry conditions.

• Time is running out for planting onions if you want a decent crop. Get your seed in this weekend.

• The advice on using washing powder as a moss killer has certainly caught the attention of many readers. I am suspecting that the cheap budget powder I have tried is not as effective as Cold Water Surf. But more interesting was the gentleman who emailed to say that he bought straight washing soda (sodium carbonate or Na2CO3 ) in bulk from Bin Inn and he tried applying it both lightly as one broadcasts lawn seed and more heavily so it was visible. Within two days, the moss was dead. It also killed the pesky liverwort. For those who care about the environment, washing soda is arguably a purer option, lacking all the extra additions of washing powder and it appears that you don’t need to be heavy handed to get a good result. You are, by the way, using these in powder form.