We are losing soil at a completely unsustainable rate.  According to The Soil Association ‘the equivalent of 30 football pitches of fertile soil every minute’ and yet it takes over 500 years to form 1 inch of top soil. 

Here in the UK we are fortunate to have deep soils due to our geological and woodland history.  This has allowed us to develop and maintain some agricultural and horticultural practices which we now know to be damaging.

Soil is incredible stuff, it’s not just a rooting medium; one tablespoon is said to have more organisms that there are people on the earth.  Most of the micro organisms are yet to be identified or understood.

Hakonechloa macra
Hakonechloa makes excellent low maintenance groundcover

Soil stores heat, holds and filters water, nutrients and gases.  It contains mycorrhizae which creates symbiotic relationships between plants and trees.  Then there’s fungi, nematodes, insects, earthworms, slugs and snails. 

Soil also stores carbon.  The more we work with and disturb with soil the more carbon we release and the more we damage the soil structure.  We also have to consider the impact of using diggers and reshaping the contours of our patches, there is often a price to pay also in terms of interrupting natural drainage.

Its a tricky thing to come to terms with as a gardener.

We also know that woody plants (shrubs and trees), absorb carbon dioxide as they grow, locking carbon in their cells (this is why we plant trees to offset our carbon footprint). Also plant roots stabilise and protect the soil they inhabit. 

Arit Anderson inspired me with the idea of “using gardens as a carbon store’ when she spoke passionately on sustainability and the choices we can make or influence.  We can choose to select our planting with this in mind.

Plant things which will do the work for you; weeds aren’t really a problem once the soil is occupied.  Ground cover planting can include shrubs as well and low herbaceous plants.

Gardeners can learn from the concepts of agroforestry and forest gardening.  Choosing perennial and woody planting as an important strategy to both store carbon, and protect our soils from the disruption of annual sowing and planting.

So protect your soil; only dig when you must, mulch it and cover it.

7 Favourite Plants for Drought AND What is ‘Chop & Drop’?

It’s been an interesting summer so far to say the least.  One which will be remembered for its heat and lack of rain.  It has felt like August since June, except hotter.  Here, we are scratching our heads wondering if its a blip or a sign of the times. 

I’ve been watching to see which plants are holding their own while others struggle. Established plants will generally cope better than those which have been recently transplanted. Those which are part of a lovely community can be aided by their neighbours foliage holding moist microclimate under their canopies. However some plants have flowered their socks off already and are now lay spent and a bit crispy.

Here are those I’ve noticed for doing well;

  1. Euphorbia characias wulfenii – I adore this and use it in practically every garden I can for its grey blue evergreen foliage, and architectural spring flowers. Its certainly loving this season and not bothered by the heat at all. Interestingly it wilts in hard frosts and then perks up when it thaws.

    Euphorbia characias 'Wulfenii'
    Euphorbia Characias ‘Wulfenii’
  2. Geranium macrorrhizum – Presumably these shallow rooted plants store some reserves in the woody stems which lay on the surface of the soil, or perhaps its the slightly hairy leaves that help – either way its happy in dry shade generally – and its doing just fine in my gardens.
  3. Artemesia – I often use Artemesia ‘Powis Castle’ whose silvery leaves love a hot dry, well drained spot. The fluffy foliage has a light texture, perfect to contrast bolder shapes.

    Artemesia 'Powis Castle' in foreground Winter '16
    Artemesia ‘Powis Castle’ in the foreground – still looking great during the winter
  4. Sedum – The fleshy leaves and stems are water stores and so sedums are perfectly adapted for drought, and there are many to choose from.

  5. Grasses – Ok that’s a big group of plants – my favourites ornamental grasses are all doing really well. Stipa gigantea, Stipa tenuissima, Carex testacea and Calamagrostis Karl Forester.

    Stipa tenuissima in drought tolerant border
    Stipa tenuissima, now known at Nassela tenuissima.
  6. Phlomis ruselliana – A good example of a ‘wooly plant’ – using fine hairs on it surface to help protect from the suns rays and retain moisture. The dense foliage works brilliantly at keeping the soil moist too.
  7. Poppies – Poppies have lovely tap roots which help them to tolerate prolonged dry spells. The big oriental poppies may flop, and can look a mess but try using this foliage to create mulch. Im getting into ‘chop and drop’ mulch at the allotment, and I reckon oriental poppies are a ideal candidate.

Chop & Drop is a permaculture concept – in that it mimics a natural cycle. Using fresh foliage to create a mulch and feed for the soil, and ultimately our plants. 

Simply lay leaves directly on the soil to retain moisture, and as they breakdown nutrients become available to the soil again. It doesn’t look as neat and tidy as our traditional horticultural methods but its very easy and it works.

Chop & Drop Mulch under courgette plant
My chop & drop mulch at work under a courgette plant

My light soil at the allotment is prone to drying out and blowing away, so Ive been using comfrey leaves and also dandelions (seeing as I have so many) but any leaves will work. The very best plants for this are deep tap rooted plants (hence my comfrey & dandelions) or nitrogen fixing plants such as clover (which you may have in your lawn clippings) and foliage from peas and beans.

Know your soil; Its useful to remember that many of these plants listed – are adapted to hot dry conditions, and along with this require good drainage – which is where winter can be problematic. Its really valuable to take the time to get to know your site well before planting new areas for these reasons.

When to plant; For some time Ive been advising clients to either plant in spring or autumn – to avoid lots of watering and to work with nature and avoid the struggle of the summer heat. This is not what everyone wants to hear but I don’t really believe we need to or should be watering our gardens generally let alone all summer long to establish a newly planted scheme. Of course we have special plants, pots and crops which we want to tend with a can of water now and then, no judgements here.

See my previous post for more thoughts on designing resilient gardens

Stay hydrated!