Many people associate winter, particularly from the latter part of December, as a time where getting out to work in the garden is not really much of an option. Although I think the trend is moving away from this notion, it is still a popular approach for many gardeners to have a final clear up of the garden some time in November; herbaceous plants are all cut back, beds weeded and raked, and so on.
This procedure is now commonly labelled “putting the garden to bed” which, in my opinion, is quite a strange phrase. For Wisley’s Mixed Borders, the winter season is certainly no less busy than other times of the year, and I have a significantly busy workload in the coming months. It's the perfect time to admire the structure, clear the old, lift and divide, and plan for the year ahead.
Colour and form
The borders are home to an array of different plant types, hence the name “Mixed Borders”, and by using this diverse planting style we are able to generate a visual interest for most of the year, including winter. The stars of the borders right now are arguably the grasses – particularly the miscanthus which just seamlessly flow through the beds. However, their unique tones of gold would be lost if it weren’t for the remaining structures of the neighbouring herbaceous plants such as the phlox and monardas, which use their rigid forms of deep browns to really highlight the grasses. In addition to this, many of the other plants which have been left, rather than cut back, still look brilliant in their own right – such as Thalictrum ‘Elin’ which still provides great structure, or Eupatorium capillifolium AGM which looks every bit as brilliant as it did through the summer months.
With so much still looking good in the borders there could be a temptation to refrain from too much physical work in the beds themselves and maybe just be pro-active with planning for 2017.
This is not my approach. The borders need to be clear for staking which I have scheduled for April and I can’t leave the whole cutting-back process until the last minute as it would be too much of a task, so I cut back/remove plants gradually.
The first plants to go are the half–hardies, such as many of the salvias, which were hit by some quite severe frosts and as a result lost all structure and collapsed. These are completely removed and composted as replacements that were propagated from cutting material are already growing away strongly under glass. Some of the herbaceous plants have also lost their structure, such as the persicarias. We cut these back at a similar time to when we remove the half-hardies.
Wisley's worst weed
It’s not just cutting back and removal of plants that occupy my time over winter. Many gardens are home to an unwelcome and persistent perennial weed and for us at Wisley this is bindweed.
After spending the summer months doing my best to delicately unwind the stems from the host plants I can now systematically work through the beds and physically remove the rhizomes by using a “single digging” approach. This is a fairly time–consuming task but one which we have proven to be effective, sustainable and organic, and it will make the management of the borders easier through next summer.
Division of herbaceous plants is a brilliant way for me to fill unwanted gaps in the borders, replace plants that were just not working, and generally have fun trying new plant combinations. The lifting process is also one crucial towards the eradication of bindweed as it enables me to clean through the roots.
My removal of many of the tender plants has exposed significant openings in some of the beds, meaning there is not so much structural interest left over winter. The lifting and dividing process means that I can add suitable plants to these areas and so next year I won’t be left which the gaps. I don’t add a blanket of mulch to the Mixed Border beds as the soil level is too high, but I do still add compost to the individual plants that go in over this period to aid them in effective establishment.