insideSUSSEX Magazine Issue 03 - May 2015

OUTDOORLIVING YOUR GARDEN: may cont. Lift and divide overcrowded clumps of daffodils after they have ﬂowered. Deadhead tulips and daffodils. Propagation Take softwood cuttings of tender perennials like argyranthemum, pelargonium and fuchsia; they will provide new plants for display later this summer. Perennials that are showing new shoots from the crown can be propagated via basal stem cuttings. Thin out direct sowings of hardy annuals and vegetables such as radishes. This is best done in two or three stages at fortnightly intervals. Final spacing should be between 10-20cm (4-8in), using the upper limit for tall or spreading plants, and the lower limit for smaller plants. Prick out indoor sowings when they are large enough to handle without damage. Hoe borders to prevent annual and perennial weeds from spreading and seeding themselves. Sweet peas need training and tying in to their supports to encourage them to climb and make a good display. General maintenance Apply a liquid fertiliser to spring bulbs after they have ﬂowered to encourage good ﬂowering next year, and help prevent daffodil blindness. Allow the foliage of daffodils and other spring-ﬂowering bulbs to die down naturally. Lift clumps of forget-me-not once the display wanes, and before too many seeds are released. They can become invasive if left unchecked. P ut supports in place for herbaceous plants before they are too tall, or for those – like peonies – that produce heavy blooms. Harden off plants raised from seed and cuttings by leaving them outside for gradually increasing periods of time. Start with only the warmest part of the day and build up to overnight exposure. Doing this for 10-14 days before planting them outdoors permanently (whenever the risk of frost has passed), will reduce any check to their growth while establishing their ﬁnal position. Pinch out the leading shoots on plants such as chrysanthemum and helianthus to encourage bushy plants. However, if tall thin sprays are preferred, they can be left un-pinched, perhaps removing a few buds (known as ‘disbudding’) to encourage larger blooms. Liquid feed plants in containers every two to four weeks. active this month. Tip out the rootball of suspect plants, and inspect for the creamy, orange-headed maggots, which tend to curl up into a ‘c’ shape. There are various chemical and biological controls available. Aphids can multiply rapidly during mild spells. Remove early infestations by hand to prevent the problem getting out of hand. Protect sweet pea plants in particular, as they can get sweet pea viruses. Continue to protect lily, delphinium, hosta and other susceptible plants from slugs and snails. Remove dead leaves from around the basal rosettes of alpine plants to prevent rotting. Top dress spring-ﬂowering alpines with grit or gravel to show off the plants and help prevent rotting around the neck. Keep tubs, hanging baskets and alpine troughs well watered. Use collected rainwater, or recycled grey water wherever possible. Pot on plants showing signs of being root bound. You can tip out the root balls of unhappy looking containerised specimens to see if they are indeed pot bound or if they are suffering from some other problem. Pest and disease watch Inspect lilies for red lily beetles, as the larvae can strip plants in days. Vine weevil larvae can be a serious pest of containerised plants, and become 80 The RHS is a UK charity established to share the best in gardening. Its work is driven by a simple love of plants and the belief that gardeners make the world a better place. For more information, visit www.rhs.org.uk.

insideSUSSEX Magazine Issue 03 - May 2015 | Page 80