Goddess VG bed explained
This Vegetable Growing planting bed design (growing system) is a combination of the best bits from current horticultural ideas such as wicking beds, mycorrhizal fungi symbiosis, ‘semi-raised deep beds’ (A. Titchmarsh) all combined within a “Sunken” U-Bend shaped paired planting bed 1.5m x 4m (golden ratio proportions 13ft x 5ft). The whole bed is then sun orientated along a North-to-South axis (as per commercial green houses). However, new to this combination of ideas is my Pallet wood Hydro-driver design which is acting as a low tech ‘moisture level moderator’ through controlled evaporation and my Wood chip sock bed edging idea. All crammed into a single growing system.
My allotment plot in West Essex is heavy and stony “London clay” that is unhelpfully alkaline. A mason jar soil test gives me about 45% clay to 55% sand & grit. It’s not an easy soil for a new starter and is the reason for this “Scotty, give me everything you’ve got” radical growing bed redesign. See images below to help in your visualisation before reading on.
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This growing system is all about maximising growth for annual woody-stemmed vegetable cultivars that have a high water and nutrient demand due to deep roots, bushy growth and long cropping; such as aubergines, chillies, tomatoes, cucumbers, courgettes, french beans, globe artichokes and surprisingly onions. Also, the unusual U-Bend shape gives us three planting areas all with slightly varying moisture levels, two lightly shaded long pillow beds and a full sun, open rounded end for crown type plants (eg courgettes & aubergines). For Brassica and Root vegetables its the same design except there is no need for my central Pallet wood Hydro-driver as they like it cold and wet.
The ultimate aim being a low-maintenance and high-success vegetable growing system with less disenchantment for new starters. Other considerations are ‘low cost’ and upcycling skipped materials (pallets) as well as being easy to construct by persons of all abilities with basic tools.
Importantly you should aim to only use the soil from your plot in this system along with dressing using acidifying horse manure to try to reduce the alkalinity of the clay soil and which will increase the range of vegetables that we can successfully grow.
Goddess Vegetable Growing bed – Construction guide and theory.
Imagine we have a virgin grass plot that we have just mowed in preparation for our first Goddess VG bed. We have collected the bits we need for this growing system, x2 Pallet wood Hydro-drivers, x3 filled Wood chip socks (3m) and are ready to start its assembly. Firstly we need to mark out our growing beds unique shape. Imagine you are struggling to hold a tall and wide 5′ foot x 12′ foot high arched double door (see 2nd image above), you swivel it around so you are facing directly south, you are standing at the northern end of this bed. You then let this imaginary door fall onto the ground and mark around it by digging into the turf with your spade. You have now sun-orientated your bed along a North-to-South axis. This means that both growing beds either side of the Pallet wood Hydro-drivers receive a roughly equal share of the daily sun, with the rounded end receiving full sun all day.
Using a sharpened lightweight spade we are going to surgically scalp the grass layer by removing only the green parts of the grass and are thrown onto your compost heap. Leaving as much of the top soil beneath the green layer as possible, the fibrous mat layer will be useful to add organic matter into the centre of our semi-raised deep bed. Now layout your filled Wood chip socks on the soil, one along the left hand side of our imaginary door, the second flowing around the rounded end and the third down the right hand side leaving out the the northern end side. Now starting at the northern end we are going to insert the Pallet wood Hydro-drivers along the vertical gap between the imaginary double doors (North-to-South axis) of this bed by digging a shallow 2″ trench and x2 two small round holes to match the legs of the divider to set them into, again saving the soil in a wheel barrow or on old bit of carpet. Right that’s the construction part completed. In front of you should be what looks like a U-Bend shaped shaped bed divided into 2 planting beds with an open soil bed at the rounded end. Now for the digging part.
Dig a one-spade-width trench across the northern end of this bed, almost like a door step lintel to this imaginary door. Again save the soil from this trench. Starting at about 3-4″ (inches) from the edge of this trench, dig to one spades depth and with a flick of the wrist push this thin slither of soil into your trench then work your way left-to-right and working backwards making your way towards the rounded end. Always little slither clods in a chevron herring-bone pattern which creates lots of air spaces within the soil. Do the same process in the other side of the paired bed. Now water each side (full watering can 10l) all this freshly dug soil and leave for a week to breakdown further. This deep digging between the Wood chip sock and the Pallet divider creates a sunken-well bed with pan-hard soil walls which further help to hold onto moisture.
On returning to this bed break up any large clods that remain with your spade and rake over and even riddle the top inch to remove large stones that have revealed themselves in this forced weathering. Collect them in a pile to be used to fill the void in the Pallet wood Hydro-driver at the end. We can now start to fill this bed with a mixture of riddled top soil and manure from other sacrificial parts of the plot such as under duckboard paths or heavily shaded areas that you will set aside for compost heaps and the saved soil from the trench. We fill the bed so the soil is level with the top of the wood chip sock and just above the lower slat of the Pallet wood Hydro-driver. We have followed Alan Titchmarsh’s technique for creating a “semi-raised deep bed” (unboxed) which is sort of a short cut version of double-digging (one-spit-depth-digging & half-filling).
The Wood chip socks that edge the borders help to retain the soil on this semi-raised deep bed as well as holding onto moisture and acting as water baffles creating the +positive moisture zone of the growing bed. Also within the wood chip socks are mycorrhizal fungi that are believed to have a symbiotic relationship with woody plants to provide them with essential nutrients such as phosphorus and nitrogen in a soluble form. The wood chip socks also allow us to create the unique U-Bend shape of this growing system.
The Pallet wood Hydro-drivers main task is as a moisture level moderator (Hydrostat). It achieves this using a physics principle called Stack Effect. How this works is that as the sun comes up it heats the stones and the air in this narrow and tall pallet void creates an uplift of warmed moisture heavy air. The absorbing but drying-on-one-side quality of the wooden bottom slat (-negative moisture zone) gradually exerts a hydrostatic pull across a large section of the soil bed sucking water from the moisture +positive Wood chip sock borders horizontally across the growing bed leading to moderated, non-saturated and consistent moisture levels within the growing bed. This hydrostatic pull also seems to be liberating nutrients and minerals from the soil more rapidly. In comparison to boxed-in “raised beds” with their easily over filled soil levels working against your plots natural water table and halting the natural wicking effect. In the traditional open-soil approach water is wicking away from a large surface area across your whole plot. I believe my Pallet wood Hydro-driver design helps sustain a ‘Goldilocks zone‘ of optimal moisture levels and steady transpiration.
The divider also acts a platform for treading on or hooking on attachments such as my g.easel (Gardeners Easel) 4-in-1 design; Squash Trellis, Bean frame, Windbreak and (G. Hamilton) Cloche design.
What’s so special about the ‘Pallet wood Hydro-driver’? Isn’t it just soil heaped against a half buried pallet?
The concept is similar to Keyhole Garden beds that are popular in Africa, except rather than circles it has been stretched out into a long thin U-Bend shape paired planting bed that fits better with squarish British plots. Both our designs make use of some form of centralised ‘moisture level moderating’.
This teenage African girl from Rwanda has constructed about the most effective KG design in my mind, without even thinking about the science. There is nice positive growth and appears to be low-maintenance with its guttering irrigation system.
My bed design with its recycled pallet wood Hydro-driver is easier and quicker to construct and without any of the heavy lifting that this little girl and her family have had to do. No building a one metre high mound of soil for starters (I realise this may be a requirement of the design due to heavy afternoon / early evening tropical showers).
My pallet wood Hydro-drivers are only in the soil for 7 months from early April to late September. Using the rope handles they are easily pulled out of the soil and stored under a tarpaulin for the winter and the bed is then seeded with a green manure to over winter.
History – how did the ‘Pallet wood Hydro-drivers‘ idea start?
Basically the germ of an idea started when I thought that the furrow between two parallel rows of potatoes was a waste of space. If I could insert a wooden partition between the two ridges and then heap the soil either side of this wooden partition, I wouldn’t have to spend time earthing them up. They would have a deeper section of soil in which to grow and only one sides worth of exposed potatoes would need earthing up rather than two. The cheapest (free) and most readily available wood to me was pallets.
Its was only once I started experimenting with this soil-against-a-leaky-trough way of creating planting beds and got more robust growth from my heavy clay soil that I started to realise it had a long list of advantages over the more traditional existing approaches.
Observations over the past few growing seasons: Positives and negatives of this system.
Hypothesis: Goddess VG bed = less watering and more robust growth, less failures and higher yields from ‘challenging’ clay soils.
When I first started with this design I mistakenly thought the Pallet wood Hydro-drivers (leaky trough) was mainly a way of getting water to the roots, sort of a water saving system. But once I added the wood chip sock edging it began to realise the design was acting as an optimal moisture level moderator. I was then unsure of the best way of watering this design. You notice with this system that when you scratch away the dry dusty top soil layer underneath has a dark appearance due to high moisture levels. Through experimenting and observation I found watering the soil just behind the Wood Chip sock border and then the dryer soil section just in front of the Pallet wood Hydro-drivers in an encircling drenching style seemed to work best. Seemed to kick start the hydrostatic pull as well as encouraging the plant roots to stretch out. Also helped to flush minerals down to these stretching roots tips.
Wolf Spiders love these pallet dividers for some reason. I’m not sure if this is beneficial or not. Do wolf spiders eat caterpillars? Every time I walk past them I see at least a couple scurry back under the stones in the dividers.
It does cost a little more to implement as the plastic mesh is a new idea and is approx 50p a metre and as you need 9 metres per Goddess bed thats £4.50. Also, it does take about double the amount of time to set this bed up. But obviously once set up your good-to-go for a few years.
Because the lower parts of the pallet wood Hydro-driver is made from wood it suffers from decay and rot and they tend to only last 2-3 years, Ideally the supports of the pallet wood Hydro-driver would be made from a recycled plastic lumber or plastic stakes. The slat that is buried in the soil could potentially be made out of a foam-like clay tile (55cm x 10cm) and might even exert a more consistent hydrostatic pull across the growing bed.
It is tempting to overload these narrow beds and because of the robust and steady early growth can lead to a noticeable yellowing of plants leaves due to nutrient deficiency and which means a feeding regime is a requirement for this growing system.
19/08/2017 – Update for 2017 – Possible first evidence of a noticable effect from a “Goddess vegetable growing bed”
This might be the first evidence of a noticeable effect in growth using these Goddess VG beds. I have neglected this bed this year as I spent more time on my Heras panel lean-to and my g.easel compost dalek trellis projects, only watering the plants in the first few weeks and a couple of times during very dry spells. All the sunflowers on my plot all come from the same parent plant from the year before and were all planted at the same time yet these 2 plants are taller by at least 50cm and have received only irregular watering. The white detergent bottle is on a 2.4m stake for scale. I think the tall sunflower could reach 3m easily my tallest SF ever. Also I used no plant feeds or fertilisers.
Possible evidence of blight resistance due to pallet wood munching mycorrhizal fungi? The tomato plant in the foreground of the above picture also showed robust growth. Another batch (12 spares) of these same tomatoes were planted in a block in a normal single dug bed all succumbed to blight but the x10 tomato plants that I grew next to my Pallet wood Hydro-driver separated beds were all untouched. The mycorrhizal fungi could be acting as an anti-fungal agent. I did not water into the pallet void much, irregulary around the plants. The white detergent bottle is on a 2.4m stake for scale. I think the tall sunflower could reach 3m easily my tallest SF ever. Also I used no plant feeds or fertilisers.
During the 2018 growing season I will start experimenting with feeding regimes for this Goddess bed growing system. Also perhaps look into sprinkling a palmful of “Sulphate of Potash / Ammonia” across the surface of the beds to try to reduce alkalinity in my heavy clay soil.