Peter Dowdall urges caution with certain plants, like anemone, montbretia, which can be invasive
We are heading into that time again when people will take notice of those beautiful, simple, pink and white blooms of the Wandflower or Japanese Anemone. Those familiar with the plant will shudder at the thought of it, and those who don’t know it at close quarters yet, may well bring some specimens home from the garden centre and plant in their own unsuspecting plot.
Don’t do it. Do not plant this thug in the open ground, don’t be fooled by its pretty and innocent looking flowers as it will turn into an undesirable in your garden. It will push out everything around it, bullying its neighbours in its relentless search for more space to colonise.
Anemone japonica is indeed a beautiful late summer/autumn flowering perennial, but can easily become a nuisance, so my advice is to grow it only in a pot or a raised bed where it can be contained and its gallop can be halted. You see, the flowers are so nice at this time of the year and for the next few months it is worth having, but tread, or more correctly, plant, carefully.
Anemone ‘Wild Swan’ however, does not fall into this category. Announced as New Plant of the Year at the 2011 RHS Chelsea Flower Show, this stunning little plant has been in flower now for a month or more already and will continue right into October. Growing to only about 40cm in height, it will clump up but not spread at will, like its troublesome cousins. Stunning little white flowers are produced with the most beautiful pale blue backing to each petal.
There are many flowers like the autumn anemone which will take over and with which care must be taken in their positioning. Crocosmias too, which come into their own over the next two months, can be vigorous. The common form Crocosmia x crocosmiiflora which we refer to as Montbrietia is brightening up the hedgerows of every highway and byway of Ireland at the moment, and you may be tempted to introduce a bit of ‘wild’ into your own life.
Again, be careful, it will take over, just look at how much it has spread in the ditches and hedgerows. Looks lovely in the wild and that’s where it should be left. Most of the cultivated forms are far less vigorous.
C. ‘Lucifer’, the much taller variety which produces scarlet red flowers is the most well-known of the other varieties, but it too can outgrow its allotted space so again be careful where you plant.
Vinca, Valerian and Buddleia can all become a problematic, if thought isn’t given to positioning, even though sometimes it doesn’t matter where you put them,despite being careful.
Perhaps you did plant them somewhere contained, or where you were happy for them to take over, to discover that not only do they spread by underground roots, but the seeds of many of these, and in particular the Valeriana (Valerian) and Buddleia (Butterfly Bush), spread quite easily, finding new homes even in the mortar joints of old stone walls, and in the most unlikely and seemingly inhospitable of places.
Another star of the late summer and autumn garden, which often gets forgotten is Eupatorium purpureum, commonly referred to as Joe Pye Weed. This will also bulk up and spread easily, but not to the point of being a problem like the autumn anemone.
Tall stems reaching up to 180cm in height will produce clusters of pink/purple flowers about 20cm wide. This is an important addition to the garden not just for its aesthetic beauty and its structural presence, standing majestically as it does wherever it is planted — no, its value as a food source to the bees and butterflies is what makes this scented plant an outstanding addition to any garden — if it’s large enough to take it.
Do bear in mind that an established clump could easily reach 2m in diameter, and so it’s not for small spaces, but the sight of this perennial in full flower, being gorged on by the bees and other pollinators in the sunshine is a real highlight of the late summer garden.
As the garden heads into the winter months the Joe Pye Weed still brings value with that lovely frosty, bleached and faded look, the tall stems which a few months previous held aloft fresh and vibrant flowers now hold up the seeds.
These will provide food for the finches and other small birds, making the garden a truly living space and helping yourpatch of green work in unison with the natural world around it.
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