Friday, 21 February 2014

Thought Exercises 1 Part 2

This post is the second part of Thought Exercises 1. To read part one click here.

In the last post I went thought the reasons for structuring a vegetable garden as tiered boxes, and the general structure itself. I take the thread back up again by detailing just what I meant by "optional extras" for the B boxes. To refresh your memory, here is a re-print of the schematic.

Fig. 1 Bird's-eye schematic

The additional options for boxes B that I referred to are that the inside walls could easily be designed to be put in or lifted out in stages. Why would this be useful? For greater yield of potatoes and carrots, mostly. Potatoes grow very well sideways, as everyone who has ever seen a potato field knows, but they also grow very well upwards. As in, place a potato at the bottom of a box and cover with soil as normal. The leaves and stalks will grow up and when they reach over the top, make the box taller and fill in more soil around the stalks. Keep doing this until you have reached maximum stability or plant maturity. When the plant has died back sufficiently, harvesting is a matter of pulling off the boards again and sifting through the soil. This method has been shown to yield as much as 100lb in 4 square feet, some examples of other people's explanations with diagrams can be found here and here.

The question of crop rotation always comes up and particularly with nightshades (includes potatoes, tomatoes, peppers and eggplants), but with the 'upward box' method, you can relatively easily change out the soil after a season if you do not have the luxury of being able to plant your potatoes elsewhere. Place a tarpaulin in front of the box, remove all of the boards, shovel the soil onto the tarp (harvesting can of course be done at the same time) and bring the tarp of soil to your previously chosen location. The potato box can be reset to the initial height and refilled with e.g. leaves, compost, soil, or at this particular location seaweed, finishing with a thick layer of mulch. Done in the Autumn/Fall, this will allow your bed to rest and the organic matter to finish breaking down so that in the Spring you can start the process again easily.  

Okay potatoes, but what was that about carrots? Did you kow that carrots grow  towards water? With a box with a removable side, you can place in a non-permanent bottom irrigation system consisting of two pipes, a 90-degree bend, a cap and a funnel. Again utilising the tarp method of soil movement, if you decide that the irrigation system is better suited elsewhere, you can remove all of the boards, lift out the pipes and replace the soil without resorting to back-breaking digging. For illustration, see Fig. 2. These types of beds are often referred to as wicking beds.

Fig. 2 Side schematic of bottom irrigation system

The purpose of this is to deliver water where you, the grower wants it, UNDER the carrots. Carrots that can get all the water they want from the surface, don't seem to stretch down very far as I learnt from my own experiences. But with this irrigation system, you can pour your water/compost tea etc. down the top pipe and it runs along the bottom pipe, leaking out into the soil through the drilled holes. Be sure to replace the cap (cos all kinds of flying things looove small undisturbed pools of water to breed in and no one likes mosquitoes...) and you are done!   

In previous posts we have written about the importance of planting specific groups of plants or Plant Guilds together to combat pests and to enable more vigorous growth. Companion Planting goes for the same principle, but the recipe of 'crop, feeder, protector' need not be so strictly applied. But for the example of the carrot beds, I would plant in calendula to repel root nematodes as well as the tomato hornbeetle and some leaf lettuce and onions, because you cant have enough onions. HOWEVER, unfortunately calendula apparently tends to attract slugs and spider mites (I have not seen any evidence to back this up myself, but it seems some others have). Beer traps, salt trails, and some bird perches should alleviate the problem without recourse to harsh chemicals. Again, in order to create your own Companion Planting list click here for the comprehensive list that I regularly use. 

For the potato boxes, I would be very interested in trying to grow horseardishes and shallot onions in with the potatoes and seeing how they respond to the climbing soil level. Would they also grow upwards, resulting in more elongated bulbs? Or would they simply be smothered? If anyone out there has any experience in this or is willing to give it a try, please let us know and we'll make sure you get your credit.
End Note.

So here ends Thought Exercise 1, I'm sure there will be more. I want to work through how to develop a free-standing, low-maintenance herb tower, so you may see that at some point too. Until then if you have a comment or question feel free to  use the comment box and, as always, have a great day!

Wednesday, 19 February 2014

Thought Excercises 1 Part 1

Well, it's been a long, wet, dreary winter here on the west coast of Ireland. We've been getting quite cabin fever-ish because we have not been able to get out into the garden for any real length of time, so for the last couple of days I've been putting down on paper one of the ideas I've been having for a property I know. 

To let you readers know the surroundings, this property is very exposed. It is on a peninsula jutting out into the Atlantic Ocean with zero windbreak to the North and only a few Celesters (Phormium tenax) and some houses to all other sides. There are no trees in any direction. The winter wind comes from the North, the most prevailing wind comes from from the West and the South. Most of the property is on sand, but there is good soil on the lower Southern side. However, there are extremely dense, extremely hardy grasses thickly covering the ground. The hydrology is very promising further down, between the large rocks and the dense grasses covering thick, peaty soil but more on that in a later post.

I've been wanting to finalise part of a design to make use of these opportunities. The owners want to dig in a standard, bare soil vegetable garden this year just for a few bits and pieces. However, due to the mats of grass (seen in Fig 1.), I expect the on-going labour to be substantial, i.e. it will be extremely hard to keep the garden weed-free and will require continuous vigilance. I'm not personally a big fan of having to spend every day weeding so I have been pursuing this exercise to offer an alternate method of growing food and is based using a pre-existing South-SouthEast slope along the curve of the house. 

Fig 1: Slope as is, facing W-NW

The beds would climb up the slope in tiers (fig. 2). To ensure stability and, indeed to make the planned shape, the slope would initially need to be dug down. The sod would be placed at the bottom, upside down and covered in a thick layer of cardboard or newspaper. This would lead to the grass rotting back under the beds and providing their nutrition to the soil. Cardboarding at the same time as placing the box sides will mean the cardboard can be tucked securely under the wood. This is an important consideration when building for a long-term garden as otherwise the grass will work itself up after a couple of years. The soil can either be mixed with compost at this point, or when it is put into the boxes. Given that seaweed is an abundant resource at this location, it can certainly be used to thickly mulch the top of the boxes.

Fig. 2 Birds-eye view schematic

To ensure safe and comfortable access to the garden, steps would be needed on both sides of the tiered beds from the path around the house at the top, to the level ground at the bottom. I would recommend them to be shallow enough to navigate with full arms and wide enough for a wheelbarrow. A path leading to the shed (located out of the lower left corner of Fig 2) would also make certain tasks easier. 

The form of the beds came about for both aesthetic and functional reasons. As most human adults can comfortably reach to 60cm or 2foot, there should be no place in the beds that is more than 60cm or 2foot from an access point. With this logic, the dimensions of the B boxes could be the same as the As, but that would cut down on the room to manoeuvre in the middle, which is quite important. There is a 15cm or 6inch step up from the bottom level of the A boxes to the bottom of the  B boxes, but the top of the B boxes are 60cm or 2foot above the top of the A boxes (see Fig. 3 for clarification). This gives much more depth potential for the B boxes. There are also extra options for these boxes which I will go into under Part 2 (because this post is running rather long!).

From the inside access area, Box C is 1.2m or 4foot high. This is reachable by most adults, but a bench could certainly be added to act as a step. On the path side it would be approx. 30cm or 1foot high to prevent washout from the path as well as stray footsteps. The house has sufficient gutters to not worry too much about water cascading from the roof.
The 'Optional Feature' indicated in Fig. 2 is not necessary but can be a cupboard for handtools, gloves and other miscellaneous items, maybe with a seat on top. It could also be a stand-alone herb-tower, or a place for cascading flowers. 

Fig 3: Impression of side-view, facing roughly East

Fig 3. is both an impression of what the 3-d shape should look like from the side (please excuse my attempt at curves) and a visual of what crops I would expect to do well in each box, (of course, definitely not a comprehensive list). I am a big fan of Companion Planting as you may have already guessed from previous posts and the plants are grouped to reflect this. The list that I mainly work from can be found here if you wish to browse through them and make your own in preparation for spring planting.

Okay, that's it for now, stay tuned for the second part of this Thought Exercise and as always if you have any questions or comments or need for clarification on any point, use the comment button below. Till then, have a great one!