Borders: revitalising an over-mature bed

Garden borders inherited on moving into a property often contain shrubs and perennials that have been left to their own devices. Even borders that have been planted within the last four or five years will need reviewing and revitalising. With some planning and preparation and good planting, borders can be revitalised to give year-round interest.

Revitalising an over-mature border
Revitalising an over-mature border

Quick facts

Suitable for Overgrown, weedy borders
Timing Late winter
Difficulty Moderate

Suitable for...

The guide below is suitable for borders that have become overgrown.

When to tackle an overgrown border

Borders can be worked on in late winter, or autumn on light sandy soils.

How to revitalise a border

How much work you put into revitalising a border depends largely on the time you have available and what you want to achieve. Research and planning will ensure the border is top-notch, but it’s a stage that can be skipped if you want a quicker makeover. However, it is still worth reading the planning and research sections for guidance.

Plan it on paper

  • Measure the border and draw it out on paper, ideally to scale
  • Note which areas of the border are shaded or sunny or influenced by adjacent walls or overhanging canopy

Design considerations

  • Work out what you would like to go where. Combine plants that you already have with extra structure or colour for times of year when there may be a lack of interest
  • Try not to use a plant just because ‘it’s there’. Would you have chosen it? What you leave out is as important as what you include
  • Decide in which season you would like a crescendo of flower colour. Year-round interest can be provided with bulbs, evergreens, but trying to have some flower throughout the year can result in a ‘bitty’ appearance
  • Aim for a balanced planting; around 30 percent evergreen, 70 percent deciduous offers a pleasing results
  • See our garden design pages for more inspiration

Practical considerations

  • Large shrubs are not easy to move so consider introducing replacements if large specimens are badly positioned
  • Choose plants that suit your soil and aspect and plant in groups, if possible, to give a cohesive look

Getting stuck in

  • It is best to start with a blank canvas. Dig up all the plants except those in the correct positions and ensure that the plants’ roots do not dry out. Heel them into spare ground or pot into containers
  • Prepare the soil by incorporating plenty (one or two bucketfuls per sq m or sq yd) of well-rotted manure or garden compost. A 7.5-10cm (3-4in) layer of organic matter over the whole weed-free border will condition the soil and help with establishment
  • Where organic matter is not availble or where soil is very poor potassium (potash) rich general fertiliser can be raked in at 70g per sq m (2oz per sq yd)
  • To keep the newly planted border weed free, mulch with  7.5-10cm (3-4in) layer of organic matter
  • If you are moving shrubs, resist cutting them back hard. Adapting to the move will be stressful enough
  • Assuming the soil is free of weeds, you can divide perennials and replant directly

Dealing with weeds

If the border contains invasive weeds whose roots have intertwined with those of plants you are keeping, re-using the plants may not be possible. Couch grass, ground elder and bindweed are common examples. If you can treat the foliage of the weeds, while protecting your plants, you may be able to eradicate the entwined weeds;

  • Remove as many roots by forking out as possible. Pernicious problems such as ground elder, bindweed and creeping buttercup may require chemical control
  • Prepare the border for planting and leave until spring or when regrowth appears. Fork through to remove further roots or spray the foliage with a glyphosate-based herbicide such as Roundup
  • Only when there has been a period of several weeks during the growing season (March-September) with no weed growth can replanting begin

Dividing perennials

  • Many herbaceous perennials decline in flowering performance after four or five years when it is time to divide them
  • More space can give plants such as irises, heuchera and hemerocallis a new lease of life

Pruning neglected shrubs

  • Many shrubs can be renovated by taking out older wood to encourage new shoots from the base. Examples include early flowering and summer flowering such as Philadelphus, Weigela and Deutzia
  • Evergreen shrubs such as Camellias, Choisya, Viburnum and Photinia re-shoot from old wood and can be successfully renovated over a couple of years
  • Some shrubs such as Cistus, lavender and most conifers are best replaced

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