Dig/No-dig

To dig or not to dig…that is the big question I’ve been asking myself lately.

I have six large raised beds and all of them are needing a bit of TLC in order to improve the soil and make them more productive.  As we inherited these with our home when we moved in three years ago, I have no way of knowing their history, how they were previously used, where the soil came from…I can only judge how it feels between my fingers and the results of my own growing.

In my first year of growing in these beds I soon discovered we had some issues.  The crops I sowed (potatoes, carrots, parsnips and some annual flowers for cutting) came up rather wimpy and lacking vitality.  Growth was a bit slow and stunted and although we did get some edibles and a few handfuls of flowers I realised that the growing conditions were not great.

Last October when it came to emptying and prepping the beds for winter I attempted to dig them over and realised I couldn’t get the fork more than half of the way into the soil – serious compaction.  So, on an impulse I went to my local tool hire store and rented a rotavator for a couple of days.  That was a fun one to explain to my husband aka the only one physically able to operate it for two days on six seriously compacted beds…

Here he is in action, along with my eldest who helped with moving the soil.  Apparently it’s good for the biceps, really he should thank me for the workout.

So, after rotavating each one, moving half the soil across the bed, digging right down to turn it all over, then moving the soil back again, I was able to dig down a full fork’s depth or more.  We’re talking a lot of soil movement, but I felt it was the only way to break up the compaction and create a loose enough structure to improve the growing conditions.

So this year I have definitely noticed an improvement, I believe I’ve had a better crop and healthier plants.  However I think the soil is still a bit thin and has a tendency to be very dry.  I’m not a soil expert, but it just doesn’t seem all that healthy.  More nutrients are needed and having done some research it’s clear that organic matter is the answer.

The first thing I hit upon was green manure; I’d heard vaguely about it and understood very little, assuming it was some kind of very fresh animal dung!  In fact, it’s a plant, or various kinds of fast-growing annuals or herbaceous perennials, such as alfalfa, crimson clover, buckwheat, mustard, or a combination of these and others.  You sow the seeds onto bare ground and their foliage suppresses weeds, while the roots restore nutrients into the soil and improve its structure.  Before the plants set seed and a few weeks before you want to start using the ground again for growing fruit or veg you then cut down the plants and dig them back into the soil,  This seemed like a very good idea and several months ago I took advantage of a retailer’s online seeds sale to buy a few packets of mixed green manure seeds.

However this research has also turned up a second, very interesting technique which is the complete opposite of how I’ve been treating the beds up until now: no-dig.

No-dig is a non-cultivation method of gardening and is pretty simple – you just don’t dig! The theory is that when you turn over the soil you disturb both weed seeds, bringing more of them to the surface, and the natural bacteria and structure of the soil.  With no-dig you simply smother any existing weeds with a thick mulch of organic matter, which is then taken down into the soil to enrich it by worms and other insects.  You can even plant straight into the mulch, as the seeds you sow there will be nourished enough to grow and put down roots further into the soil, below the mulch layer, giving you a nice healthy crop.  In fact, I shouldn’t be explaining this to you – I should be pointing you in the direction of the rather wonderful Charles Dowding, a very successful and knowledgeable proponent of no-dig gardening.  He’s written a number of popular books on the subject and his website and forum is also full of advice for anyone keen to try the method.

So – I have green manure and the time-pressed (and lazy) gardener in me is very interested in no-dig.  The result of all this research is a highly unscientific experiment in my own back garden allotment.