Plenty to do to prepare for winter

May is a month of transition — tidying, preparing and planning. The work done now sets the foundation for a productive and beautiful garden in the seasons to come.

Frosts are beginning to blacken dahlia and pumpkin foliage, signalling the garden’s move into its winter phase. While it may feel like everything is going downhill, the accumulated moisture will be valuable once mulch and compost are applied, locking in goodness for strong spring growth.

Focus is now on winter preparation, so cut back damaged dahlias and either lift and store tubers in a dry place or cover them with straw or compost if left in the ground. If mulching is not yet under way, cut stems and bend them over to prevent water from sitting in hollow stems and causing rot.

Autumn roses have been delightful, with rich colour from cooler nights, but they are now fading. Remove spent petals, but leave seed heads (hips) to help harden the wood ahead of pruning in July. Avoid feeding roses now as new growth is not needed. A light dressing of lime is beneficial, and now is the time to prepare soil for new bare-root roses by adding compost and manure.

Lime can be applied around plants that enjoy sweeter soil including herbs, lavender, carnations, clematis, sweet peas and pink hydrangeas. Let the rain wash it in. For sweet peas and clematis, prepare deep, manure-filled trenches now to support strong growth later.

Take time to tidy pots and refresh tired plantings. Leggy succulents can be broken up and replanted, each "baby" forming a new plant. They are ideal for winter containers, especially planted around spring bulbs like hyacinths, providing interest before bulbs emerge.

Continue planting winter colour such as pansies, primulas and polyanthus in beds and pots.

As the month progresses, ensure shallow-rooted plants like rhododendrons, azaleas, camellias and maples are well-watered before the soil cools further, as moist soil helps protect roots.

Weeds are still active but easily removed while the ground is soft. Keep on top of tidying, dividing perennials, and replanting where needed.

Tulips can be planted now and are well worth the wait. For impact, combine red tulips with blue forget-me-nots. Sow seed now for a co-ordinated spring display. Established forget-me-nots can be cut back rather than removed, encouraging fresh growth.

May is a good time to "wrench" trees you intend to move in winter by partially severing roots on one side and backfilling with compost to encourage feeder root development before transplanting.

Lawns will still be growing due to mild, wet conditions. Keep mower blades slightly raised and use the mower to collect fallen leaves. Growth will slow as temperatures drop.

Fruit trees are nearing dormancy. Apply lime and potash around the drip line to improve soil condition and support next season’s fruiting. Collect walnuts each morning before rats get them and store to dry them.

In the vegetable garden, broad beans can still be sown throughout May as they germinate well in cold soil — plant in double rows for support. Garlic, shallots and rhubarb can also be planted, particularly in coastal areas. Clear spent crops, dig in green material and compost and add gypsum to heavy soils, leaving them open for winter frosts to improve structure.