Although the month of May marks the official start of the summer season, it is usually prevailing weather conditions at the time which will determine what the season might be? By this time, much of the early spring growth will be manifesting itself with plenty of new emerging blooms and the rapid growth and re-emergence of beautiful new leaf growth, new buds and flowers of herbaceous perennial shrubs and flowers is a welcome sight to fill the gaps left by winter dormancy.
May offers the gardener a temporary lull to take stock between the initial burst of spring activity and the summer garden schedule. The principal tasks this month will be to control the growth of annual weeds and maintain the lawn areas.
Other key tasks this month:
- Annual weeds will rapidly appear now and there are various means of control available. Mulching with bark or pebbles or home-made compost can help. Simply pulling out weeds by hand is tedious and reasonably successful, but you must remove the root also otherwise the chances of the weed re-growing are high. Hoeing on dry days is less backbreaking and more successful as the hoed weeds will dry out and die quickly. A less labour intensive method is to use a systemic weedkiller (kills foliage and root) but be careful and avoid killing nearby plants.
- Shrubs are beginning to look their best now and the sight and scent of flowering shrubs such as Choisya Mexican Sundance or Choisya ternata simply captivating. Extend the enjoyment by considering complementary planting around perimeter of shrubs, using summer flowering annuals or reliable perennials like Primula can offer good contrast and additional seasonal interest.
- May is a busy period for the lawn area, regular mowing, weeding, feeding (apply a fertiliser high in nitrogen essential for good grass growth) and watering (if required) is peaking now at this time of the year.
- Although the risk of frost is still a possibility, it is a good time to start preparing and planting up the pots and containers for summer flowering displays. Ensure that the growing medium is suitable for the plant, most are lime tolerant but popular acid loving plants (Skimmia, Pieris, Azaleas, Rhododenrons, Leucothe etc) will require specific soil or growing conditions i.e. ericaceous soils. Most plants prefer reasonably free draining soil conditions and add a layer of bark or pebble mulch to soil layer, which will help to conserve moisture.
- May marks the beginning of planting out summer flowering Dahlia tubers.
- Now is a good time to give ornamental hedges such as Box a trim to help retain shape.
- Check all plants in newly planted borders/gardens regularly to ensure there are no problems due to lack of moisture, or may have become loose in the ground because of windy conditions etc
- Only after flowering has finished, now is a very good time to prune to preferred size and shape spring flowering shrubs (Forsythia, Kerria, Spirea etc).
- Spray roses which are vulnerable to blackspot disease, especially in damper regions.