When No Dig equals No Grow

I’ve been a convert to No Dig for the last few years. I first encountered it through the work of Charles Dowding, whose years growing for sale and home consumption, with a healthy splash of trialling, have shown clear benefits to the methodology. No Dig isn’t always about producing more, particularly, so much as working the earth less. This frees up time to enjoy your land and crops and harvest more efficiently. It also replicates Nature; the spreading of compost annually mirrors the drop of decaying matter.

However, in the creation of new veg beds this year, No Dig equals No Grow for me.

This has been frustrating for me to say the least, especially having practised No Dig before in my Cressbrook garden. I was able to plant lettuces, calabrese and broad beans straight in, no problem.

I also successfully grew cut flowers in No Dig beds set up early 2022. Everything thrived, from cornflowers to dahlias, sweet peas to bells of Ireland.

Not so in 2023.

No Dig equals No Grow

In early April I took receipt of two tonnes of JPR Gold – a combination of well-rotted cow manure and finely shredded bark. It was laid over cardboard, itself laid over sand above clay soil. The site had previously been a patio.

A variety of vegetables have been started off indoors and planted into it since April: beetroot, mangetout peas, sweetcorn, courgettes, cucumbers and squash. I also planted shop-bought kale, broccoli and lettuce seedlings, and direct sowed borlotti beans, turnips, parsnips, carrots and radish.

The direct sown seeds took weeks to germinate, and since showing their seed leaves, have been frozen in time. Similarly the lettuce, pea, kale and broccoli have paused. It isn’t that they’ve died – they’re just not growing.

The squash plants, put out after the last of the frosty nights had gone in late May, have been knocked back though. One of the ‘Muscade de Provence’ lost all but one young leaf, and one of the cucumber plants has withered away.

Those direct sown seedlings which got stuck at two seed leaves have been gradually decimated by unseen assailants. It’s clearly slugs and snails for the most part, as the tell-tale slime trails were evident some mornings.

On pulling withered and stunted plants, I’ve found root systems that haven’t spread since planting. But I’m not sure why this is…

Possible causes

I’ve wondered if it’s the sand beneath the No Dig beds. However, Charles Dowding remarks in a couple of places that a convert to No Dig on almost pure sand in the US has had bountiful harvests with nothing more than compost laid over it. Not that then.

I also questioned whether the “well-rotted cow manure” in the JPR Gold was in fact not rotten enough. Perhaps it was burning the young plants. I doubt this though, as the compost didn’t smell at all upon delivery.

I’m left with two possibilities.

First is that the shredded bark content is still decomposing. This often results in poor plant growth because the microbes involved in decomposition use a lot of nitrogen to work, so that nitrogen is not available to plants. This could explain the chlorosis (yellowing) and bluish tints to many of the plants.

The second possibility is that the JPR Gold is too effective at holding water, especially above the compacted sand layer. Too much water in the ground means too little air. Roots need oxygen to grow and pores to travel through. Without this, the roots stagnate and eventually rot away.

Hindsight

Addendum: I contacted the providers about this issue, and was informed it is not appropriate as growing medium for No Dig. They say it has no binding structure without being mixed into the soil manually, hence roots are not anchoring and developing. This has shaken my No Dig understanding a little, as I believed any organic matter, if well enough rotted, would be cohesive enough to hold plants!

Most likely it’s a combination of these two factors. With hindsight I would have ordered the JPR Gold mixed with topsoil to create the new beds. This combination would most likely have been looser in texture, so freer draining, while still holding onto adequate moisture.

The most assured way to No Dig compost is invariably to create your own.

I’ll persevere, and come late autumn will spread some vegetative compost over the top of the beds. Hopefully by then soil organisms will be mixing the matter for me, and any nitrogen theft will be over.

It’s for the sake of soil organisms that I stick with No Dig. It makes complete sense to me to emulate Nature, by spreading organic matter and leaving the invisible communities of microorganisms and creepy crawlies to do as Nature intended.