Spring is fast approaching here at RHS Garden Wisley, and before long the herbaceous perennials that we all love so much in the height of summer will be starting to emerge from their winter slumber. But are you prepared for the onslaught of fresh growth?
Thanks to a good helping of homemade compost, a few handfuls of fertiliser and the odd April shower, we can expect plenty of lush growth from our perennials by the time that May gets here.
The plants might think that they’ve never had it so good, but then, disaster! A summer storm brews up and all that growth gets knocked down, leaving a sorry sight of rain-splashed blooms on the ground. And what is the answer to this problem? Staking, of course. There are many ways of staking; some opt for the simple bamboo cane and garden twine treatment, others for pre-made metal structures, and I’ve even seen chicken wire used before.
Here at RHS Garden Wisley we use three different methods. The first is metal link stakes, ideal for areas that will be out of sight by late summer or as a quick fix if time is short. The second is post and pea netting, great for tall leggy perennials such as Aster and Helenium. And the final and my favourite method is birch staking, which provides attractive supports that are visible in early summer and are great for clumps of perennials like Persicaria and Galega.
How do I know if I need to stake my plants?
Well, it depends on how tall the plant will be by summer and how much of a spoilt lifestyle it has enjoyed. Most perennials that will grow more than 60cm (2ft) in height are probably going to need some help, especially if they have lush growth and large flowers. But a big factor is their growing conditions. Interestingly, at Wisley we have many plants growing in our Mixed Borders that require staking, yet some of the same plants growing in the Glasshouse Borders don’t require staking. This is where the spoilt-versus-tough- love shows, with the Mixed Borders having the benefit of dark humus-rich soils, regular feeding and irrigation if there is no rain compared to the Glasshouse Borders’ poor soil, no feeding and no irrigation.
So to my favourite staking method, using birch. At Wisley we are fortunate enough to have a good local supply of silver birch saplings growing on a nearby area owned by the Surrey Wildlife Trust.
Every January we harvest hundreds of bundles of birch, which we use on the Mixed Borders to create woven plant supports for the season. Over the years that we have used natural materials for supports, the birch has become a regular fixture for the borders, and visitors enjoy the sight. The structural and often artistic feel that the birch supports provide complements the plants and interest until the first flowers of summer.
By high summer all of the supports are absorbed among the foliage of the plants - visitors are amazed when they ask “how do the plants stay upright?” and I part a clump of Aster to show them the supports tucked inside. Even after the first frosts and throughout winter the supports still work, especially if you wish to keep stems and seed heads such as Echinops or Eupatorium for winter interest.
Now in March we can see signs of herbaceous perennials starting to emerge and we can start staking. So from mid-March until early May we have the perfect window to stake.
It is important to remember that staking is there for support, so give your plants a little room to grow into otherwise they can look 'as trussed up as a turkey' as a colleague of mine used to say. It’s all about support rather than confining.
So give it a go and give your plants some help to lean on…
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