It's Raining Gardens.

I have been thinking about our soggy drought.  Obviously our weather patterns are changing and seem to be becoming more extreme.  It is a sad fact of life and our gardens and gardening habits need to adapt to get the best out of what is happening.  It now seems 'normal' to have very dry periods broken by extremely wet intervals.

All the recent press about Drought Gardening is well and good, but I don't think it quite covers what is happening here and now, in Devon.  We can certainly plant drought tolerant species but we need to ensure that they either have very free draining soil for when the deluges arrive (assuming they are desert adapted), or that they are able to cope with extreme wet, such as we have had in the past few days.

Given our recent weather it is quite likely to be raining as you read this.  If it is, look outside at your terrace or a paved area.  For every 1 millimetre of rain that falls on a square metre of paving 1 litre of water will be collected.  So in a ‘standard storm’ (or frog-strangling downpour) 30 litres of water will fall on every square metre of garden - paved or otherwise.  That's a lot of water.

All this has to go somewhere.  It can either go straight into the drains, which can easily become overwhelmed and cause flooding, or we can use it to create a beautiful type of garden called a Rain Garden.

The idea of designing a garden, specifically as a Rain Garden is relatively new and has been developing only over the past 20 years.  A Rain Garden tries to keep as much rain water as possible out of the sewage and mains drainage systems allowing it to drain away naturally and slowly. 

Rain Gardens have a lot of points in their favour:

·         They look beautiful.

·         They are good for wildlife.

·         They help prevent floods.

·         They help top up the aquifers.

Rain Gardens can be designed in either a formal or informal style which must look attractive in both wet and dry weather.

The basic principal is to keep as much rainwater as possible on the property and to keep it visible. 

The starting point is rain coming off a roof or terrace.  This can go down the usual guttering or rain chains and can then be gathered into storm water planters.  These can be in any style at all, as long as they have an overflow mechanism for when there is too much water for them to absorb.  When this happens the next stage of water management starts.  This can be in the form of rills or streams which will direct the water from the planters into the Rain Garden itself.  This is basically an absorbent planted depression or hollow which acts as a big sponge.  It needs to have very well drained soil and plants that can cope with being soaked for periods.  If there is so much rain that this area overflows the water can then be directed to a pond which can hold the rainwater until it can gently drain away naturally over a period of days.  Alternatively the pond can be lined and used as a semi permanent feature in the garden. 

This style of garden is flexible enough to cope with periods of drought but will really come into its own when the heavens open and it becomes a watery haven.  You could even look at it as getting two gardens for the price of one, which surely has to be a good thing.

  

Watch Out - there's a drought about

It may not have hit us yet in Devon but impending hosepipe bans and the drought which is affecting a lot of the UK is a subject which needs to be addressed.

Our climate is changing.  We are seeing longer, dryer and generally hotter, summers punctuated by period of intense rainfall.

Water is an increasingly expensive resource which needs to be conserved.

Drought proof gardening requires a shift of mindset away from the traditional English garden with its lushly planted herbaceous boarders and sweeping lawns.  Look to those areas of the world where nature is dealing with drought and gain inspiration and planting ideas from them.  California, South Africa and the Mediterranean are all places which have supplied our gardens with hundreds of plant species which thrive in exactly these conditions.

There are some common themes to successful drought tolerant gardens, relating to creating the right environment and the types of plants that you use:

Stone, rocks and gravel are essential either used for paving, courtyard walls, as a mulch, to help with drainage or as a planting medium.

With limited moisture, plants naturally grow more widely spaced which has the added benefit of allowing their individual shape and form to be appreciated.  Many are very dramatic and architectural.

A lot of the plants which are adapted to these conditions have silver/grey or fleshy leaves which help conserve moisture.  They are often slow growing and/or evergreen.

Drought tolerant plants tend to flower during spring and early summer when there is still enough moisture to enable them to do so successfully.  It is therefore really important that the structure of the garden provides interest outside these periods.

As with all aspects of garden design, preparation is vital.  The bones or framework of the garden have to be strong enough to support this dramatic style.  The soil needs to be prepared before planting and also needs to be well drained.  Once this is complete then it is very much up to personal taste as to what style of planting is done. 

There are hundreds of plants which will thrive in these conditions.  Simply think of the different types of gardens and landscapes found in the Mediterranean.  They can be romantic and rustic with masses of lavender, soft billowing grasses and aromatic herbs or very minimal and architectural using dramatic cardoons, Eryngium and succulents.