Thursday, 27 April 2017

Small Pond Installations for Irrigation and Wildlife - Part 1

We've done a couple of pond installations recently, one for our new perennial polyculture trial garden (Ataraxia) and another for a permaculture farm/orchard I designed for Catherine Zanev and Adjmal Dullo from Venets Ltd.


Wildlife ponds in our gardens

I thought I'd write a post to share our experience and provide an overview of our pond design and installation process. In this post we'll look at locating a pond, pond design and pond digging and in a future post I'll write about lining, planting and landscaping the pond.

Introduction 


In both the recent ponds we dug we hired a machine and driver to carry out the dig. Previous ponds we've dug by hand. With some willing help a 6 x 4 x 1.5 m pond is very do-able and I'd estimate that  3-4 people with good tools would take about 8- 10 hrs on moderately light soils, probably longer in clay.

The Pond in the Paulownia Garden - dug by hands 

The recent ponds we made required 3 and 4 m depths and were larger in surface area so we opted for machines. For the pond in the new garden (Ataraxia) we used a mini digger and it took us approximately 7 hours to dig 10 m x 6 m x 3.5 m. The soil is sandy silt full with smooth boulders ranging in size from basketballs to tennis balls.  

Larzar and his mini-digger at work in the new perennial polyculture trial garden (Ataraxia)

For Catherine's pond we used a JCB excavator. I was planning to use a JCB back hoe but the excavator turned up and actually I was really pleased with the machine. Perhaps the front bucket on the back hoe would have cleared the top soil a little faster but the excavator made a great job of...er.... excavating :)  It took around 5 hours to dig a 12 m x 6 m x 4 m hole, to level the 2 m wide pond walls, make a 30 m inlet swale and a 15 meter spillway. The soil is heavy clay.


The JCB excavator starting the dig at Catherine Zanev's permaculture farm  

So here's an overview of our design and installation process.


Pond Design and Installation Overview


Check the legalities and regulations of building a pond in your area. For ponds containing over 200 m3 of water and ponds on steep slopes with retaining walls that will bear a lot of weight, it's best to seek professional advice and guidance before you start.

Selecting a Location


Topography - Based on the topography of the site we select the optimal location for the ponds and work out the positions of the inlet (where the pond receives water) and outlet (the exit point for overflow from the pond).

Google earth  image of Ataraxia with 1 m contour intervals extracted from a Digital Terrain Map (DTM) DTM supplied by Geodetect, data extracted by georgipavlov.net


Pond placement in the north east corner of the site is the highest point of the site and provides opportunity to siphon water from the pond for irrigation. We have access to a stream that can be diverted from the N.E to fill the pond. The beds are placed more or less on contour to ease irrigation.     


Surroundings - The pond location will benefit from protection from strong winds and some shade (to reduce evaporation). Having lots of deciduous and fruiting trees around the pond will result in large quantities of leaf and fruit falling into the pond that can cause eutrophic conditions unless cleared, and digging a pond around established trees will also inevitably damage the roots of the trees.


What is the pond for?


Clarifying your objectives for having a pond is important and determines the shape and size of the design.

If you would like to encourage wildlife you will need to provide various depths within the pond to cater for a range of aquatic plants and you'll need a gentle slope for animals to enter and exit. Eventually, adding some features such as tree stumps or hollow rocks to the pond will provide hiding places for fish and other pond life and basking territory for amphibians.


The four categories of plants that should be present in a wildlife pond  Emergents (Marginal Plants) - Deep Marginals (Rooted Floating Plants) - Oxygenators (submerged plants) - Floaters (free floating plants) 

Installing a pond is probably the single most effective thing you can do in a garden to enhance biodiversity and wildlife and the majority of the wildlife that will be attracted to the pond will be of great benefit to your garden or farm, i.e pollinators and pest predators. For a wildlife pond a maximum depth of 1.3 - 1.5 m is adequate. At this depth most aquatic organisms including European carp -Cyprinus carpio can survive the winter.

Frogs and Toads are excellent predators of slugs and grubs in the vegetable garden 

If you need the pond for irrigation and do not have another source of water available it's best to dig deeper both to store more water and to moderate the water temperature to reduce the evaporation rates. Deep water stays cooler for longer and moderates the temperature of the surface water and water in the shallows that will warm much faster and evaporate quickly.
  

Sketching the Pond Design



I make a few simple drawings showing the boundaries and dimensions including an overhead view and a cross section of the width and length. This helps clarify how the pond will look and function. If using a hired machine/driver these sketches will also help communicate your vision.

The below sketches are for the pond we installed at Catherine Zanev's farm where the objective was to store rainwater from surface runoff during storm events for irrigation, but also to provide habitat for a range of wildlife and aquatic plants, hence we included shelves and beaches in the design.  

Overhead sketch
   
Cross section sketch 

Marking the shape of the pond and where the depth changes occur on the land also really helps.  A long rope works well for this as do stakes connected with string or spray paint.  

Installation Day


Pegging out - Get on site well before the machine arrives and mark clearly all relevant features of the pond such as the perimeter, the width of the wall, the path of the inlet and spillway, the locations of depth variation and the highest and lowest points of the land that the pond will be placed.

Me and Stoyan Georgiev pegging out the spillway using a transit level.

Planning  Soil Deposits
- Select an area where the top soil and excess sub soil can be stored. Most of the sub soil can be used for a wall on the lower section of the pond (if working on a slope) or as bank around the perimeter of the pond if working on level ground and your potential water source is higher than the wall height. In some cases you may have excess soil. Have a plan for where to put it and how you will get it there.

It's also worth planning the route for the machine to enter and work in to avoid soil compaction and damage as much as possible and to restrict this to as small a space as possible.


Communicate the plan - When the driver arrives explain exactly what you want to do and why you want to do it as clearly as possible before works begins. An experienced operator will most probably have a good understanding of the fundamentals and may be able to offer some advice so it's a good idea to invite the drivers opinion.

Remove Top Soil - First off remove the top soil from the pond area and from the area around the pond where the wall will be placed, The top soil is very valuable and can be used to dress the excavation at the end, helping to hasten revegetation. It can also be used in another area of the garden/farm.  


30- 40 cm  of top soil is removed and stored separately for later use 
Start digging from an outside edge and dig down to the deepest part of the pond to assess the soil profile and depth. It may be you have planned 4 m depth but hit rock after 3 m. Once you have established the depth you can start to distribute the sub soil to build up the lower sides of the pond. The excavator made a great job of compressing the various layers of soil that were piled up on the edges with the flat side of the bucket. A 2 m wide wall base is very secure for a pond of this size (12 m x 6 m x 4 m).



Sub soil used to build a 2m wide retaining wall 
Get the levels right  - If your water input is at ground level remember the highest level the pond water will reach will be no higher than the input source and once the pond fills to this level it will start to back flood.

An overflow route that will slowly disperse the water should be implemented.  For the above pond design we lowered a section in the wall to disperse overflow into a 16 m swale that runs just slightly off contour into the adjacent fields.

Having a transit level on site you can quickly check levels as you go to make sure the walls are high enough and that the overflow is where it should be.

We used the top soil to build a berm slight off contour to disperse any potential overflow water into the fields. 

Any earthworks that we are sure won't be disturbed in the near future we re-apply the top soil to and sow with a cover crop. In this case we used Trifolium repens - White Clover at a rate of 1.5g /m2 for the inlet and outlet swales.  


Trifolium repens - White Clover  


Following the dig, the deposited soil will sink and settle over the next few weeks. A few heavy rains will encourage the settling of the soil. After the soil has settled, we check the levels  again and make any necessary adjustments before lining the pond.

In a following post we'll look at liner options, how to install a liner, planting out the pond, landscaping the pond banks/earthworks and pond maintenance.

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Saturday, 15 April 2017

Polyculture Study 2017 - Starting the Growing Season

After a long cold winter it's great to get started on the third year of our polyculture study and to welcome this year's team to the project.

Gabriele and Fergus are the first to join us, along with old friends Ute, Simon, Kartini, Marlene and Karl, who have purchased some land within an area we are working towards protecting. We've been pretty busy developing the new perennial polyculture garden, preparing the beds in the market garden and clearing plots for some new tree plantings.



Here's a review of what we've been up to in the market garden so far and in a future post I'll write about developments in the new trial gardens.

The Market Garden 


This year we'll be running three annual polycultures trials in the market garden, the usual Zeno, some changes to last year's Epictetus polyculture, and a variation on that theme called  Aurelius.

Produce from the gardens will be offered in veggie boxes from mid June - late November and we still have room for few more subscriptions. so if you are interested in a weekly fresh box of fruits and vegetables please send us an email.



Starting the Season - After the last harvest and end of season tidy up in November the market garden has been left to grow wild until the beginning of the new season in April. As you can see in the photo below a range of native plants establish on the beds providing some winter ground cover, excellent pollinator forage and a good supply of biomass that we chop and drop on the surface before applying the new mulch and plant out the crops.

The native plants on the edge of the beds are encouraged to grow throughout the year. They provide a partial buffer to the snails and slugs venturing in for our leafy crops, habitat to a range of ground dwelling invertebrates and a continual source of biomass as we mow them throughout the growing season and apply the trimmings to the surface.  

The annual beds have some excellent patches of native annuals providing early pollinator forage and habitat to a range of invertebrates.
Our first step of the new season is to take soil samples for lab analysis. It's encouraging to see Phosphorous (P) and Potassium (K) levels increasing and pH stable within the optimal range for vegetable production.  Even more encouraging is the jump in levels of P and K from the November analysis before any compost has been added to the beds and after harvesting over 330 kg of produce from the beds last year. See here for detailed report of last year's records.


2016
Nitrogen mg/kgPhosphorous - Potassium mg/100g
March (before adding compost)pH (KCI)N03N NH4NP205K20
6.654.435.798825.2
November (after final harvest)pH (KCI)N03N NH4NP205K20
6.618.173.8344.122.1
2017
Nitrogen mg/kgPhosphorous - Potassium mg/100g
March (before adding compost)pH (KCI)N03N NH4NP205K20
6.7325.14.8514739.6

Soil analysis from March 2016 - March 2017  

A soil examination is used to assess observable properties of the soil. We use the Northern Rivers Soil Health card to do this and since records begun in 2015 we are seeing year on year improvements. See here for our records. The simple test looks at drainage, structure, soil biology, ground cover aggregate stability and more.

Gabriele and Fergus looking at the soil structure from one of 5 samples taken from the beds 

The next step is to get the beds ready for the incoming crops. First we apply a hand trowel (70-100 g) of wood ash (the remains of our winter fuel) per m2 of bed. You can read more about the benefits of wood ash in our previous blog post here. The beds are then lightly forked over to relieve compaction and remove any rhizomatous plants that may have established (such as nettles and mints) minimising the spreading of these plants in the cultivation zones. The rhizomatous plants go on a compost pile while all of the other local volunteer plants are cut at the base and applied as mulch to surface of the bed.

Forking over the beds to relieve compaction
Next we added compost to two of our beds, a wheelbarrow full is applied to the surface (approx 80L) of 3m2 of our beds i.e 26.5L /m2.


These beds will be used for two vegetable polycultures we are testing - Epictetus and Aurelius. The other four trial beds will host a polyculture we call Zeno. Two of the four beds will consist of the polyculture and two beds will be the same plants but planted in blocks (see below).


As there is still a thick mulch cover on the Zeno beds and the soil analysis shows high levels of  P and K, compost will be added to these beds when we plant out the crops as young transplants as opposed to blanket covering the entire beds with 20L per m2 as per usual.

We've had the tomato seedlings growing since late Feb inside the house under an LED grow lamp. It's good for keeping the seedlings upright indoors for initial stage before thinning and the 15 W lamp 50 cm by 50 cm can grow on 1000's of seedlings. The units cost around €25 each from ebay and has lasted 3 years so far without problems.

The first week of April we set up a hoop tunnel and transplanted the 4-6 cm high tomato seedlings. When they reach  15-20 cm in the hoop tunnel, around early May, we planned to plant them into their permanent positions. Unfortunately, I set the hoop tunnel up in the wrong place and an untimely wicked wind from the North flayed our plans and destroyed nearly all of the 450 or so tomato cultivars. So this year we'll be buying tomato transplants from the neighbours.  

Left - Right - Tomato seedlings under LED - Gabriele tilling the hoop tunnel bed before the seedlings go in - Fergus planting out the seedlings

The other crops such as beans and squash for the Zeno polyculture and control bed we'll grow in flats this year. In previous years we have sown in nests into the mulch but the cool and wet springs resulted in many of the Fabaceae (bean)  and Cucurbitaceae (squash) seeds (squash in particular don't tolerate heavy moisture) rotting in the ground, hence the change of plan.

Ute and Fergus filling the flats with a 50% compost 50% sand mix 
We're using flats with 28 cells of 70 x 70 x 80 mm per cell. Approximately 6 L of medium is needed to fill each tray. The medium we use is 50% compost 50% river sand which makes the trays quite heavy, but works really well for raising seeds and rearing on plants.

Many of our leafy crops were sown in a hoop tunnel in late March and will be planted into the beds when they reach 15-20 cm high. We're dense sowing a variety of salads directly into the beds for "cut and come again" greens and beetroots, swedes, parsnips and carrots as they don't appreciate transplanting.

Brassicacae hoop tunnel.

For a full list of annual crops we're growing in the gardens this years see below.


The Forest Garden 

The perennial plants are nearly all in leaf now and many are in flower. We've been topping up the mulch around the young trees including some new autumn plantings,  two Bulgarian cultivars of Apple 'Karastoyanka' and 'Aiviana' and two plum cultivars 'Angelino' and 'Santa Rosa'

A new nitrogen fixing element has been added to the forest garden Alnus cordata - Italian alder, that we'll be experimenting with on fast coppice cycles on one half of our irrigation swale.  Wild garlic has been planted into the Plum/Hazel thicket which hopefully will share the space with the existing Ivy, but provide a good spreading cover in the area during the spring in years to come.


Alnus cordata - Italian Alder 

The fruit trees in the gardens are all very busy reproducing and not at all shy about it either :)

Left to right - Peach - Plum - Crab Apple - Jap Quince and Pear 

 


Regenerative Landscape Design Course 

Annual Crop List for 2017


Latin name Common Name Familly
Tagetes erectaAfrican Marigold -AAsteraceae
Tagetes patula
French Marigold -A
Asteraceae
Calendula officinalisPot Marigold Asteraceae
Helianthus anuussSunflowerAsteraceae
Lactuca sativaLettuceAsteraceae
Cucurbita pepoCourgette Zucchini
Izobilna
Cucurbitaceae
Cucurbita moschataSquash Waltham ButternutsCucurbitaceae
Cucurbita pepoSummer Squash
White Bush Scallop
Cucurbitaceae
Cucurbita pepoCourgette Zucchini
Black Beauty
Cucurbitaceae
Cucurbita pepoWinter Squash
Local Winter Squash
Cucurbitaceae
Phaseolus vulgarisFrench Climbing Bean
Cobra Beans
Fabaceae
Phaseolus vulgarisFrench Climbing Bean
Hristo's Beans
Fabaceae
Phaseolus coccineusRunner Bean
'Moonlight'
Fabaceae
Phaseolus vulgarisDwarf Yellow Bean
"Rocquencourt"
Fabaceae
Phaseolus vulgarisDwarf French Bean
"Slenderette"
Fabaceae
Solanum lycopersicumRozava Magia Solanaceae
Solanum lycopersicumGolden Queen Solanaceae
Solanum lycopersicumBlack Krim Solanaceae
Solanum lycopersicumMixed Saved Solanaceae
Solanum lycopersicumBeaute Blanche Solanaceae
Solanum lycopersicumLocal Hierloom Solanaceae
Solanum lycopersicumTigerella Solanaceae
Solanum lycopersicumPaulina BG F1Solanaceae
Solanum lycopersicumMirabel -Yellow CherrySolanaceae
Capsicum frutescens ChilliSolanaceae
Ocimum basilciumSweet Genovese BasilLamiaceae
Pastinaca sativaParsnip
White Gem
Apiaceae
Daucus carotaCarrots
Autumn King
Apiaceae
Petroselinum crispumParsleyApiaceae
Anethum graveolensDillApiaceae
Apium graveolens var. rapaceumCeleriac
Giant Prague
Apiaceae
Raphanus sativusRadishBrassicaceae
Raphanus sativusJapanese Radish
Mooli Minowase
Brassicaceae
Brassica napusKale - Borecole
'Siberian'
Brassicaceae
Brassica napusKale - Borecole
'Scarlet'
Brassicaceae
Brassica oleracea Kohlrabi -
White Vienna
Brassicaceae
Brassica oleracea Kohlrabi
Purple Vienna
Brassicaceae
Brassica oleracea Broccoli
Romanesco Ottobrino
Brassicaceae
Brassica oleracea Broccoli
Calabrese
Brassicaceae
Eruca sativaRocket
Wild Rocket
Brassicaceae
Brassica junceaMustard
Red Giant
Brassicaceae
Brassica rapa subsp. rapaTurnip
Purple Top White Globe
Brassicaceae
Brassica rapa subsp. rapaTurnip
Milan White
Brassicaceae
Brassica napus subsp. rapiferaSwede
Marian
Brassicaceae
Beta vulgaris subsp. ciclaSwiss Chard
Rainbow Mix
Amaranthaceae
Beta vulgarisBeetroot
Boltardy
Amaranthaceae
Beta vulgarisBeetroot
Saved seed
Amaranthaceae
Atriplex hortensisOrach
Saved seed
Amaranthaceae
Allium cepaWhite Onion Amaryllidaceae
Allium sativumGarlic
Market Bulbs
Amaryllidaceae
Zea maysCorn
Red
Poaceae
Zea maysCorn
Biege
Poaceae
Zea maysCorn
Popping Corn
Poaceae
Zea maysCorn
Saccharata
Poaceae


Our Annual Polycultures - Epictetus

Annual Polyculture - Epictetus



We tried this polyculture for the first time in 2016 (see here for results). It's basically a strip pattern of various vegetables from different plant families arranged to reduce pests and diseases, optimize space and nutrient share whilst respecting the individual plant needs for space and light.

Epictetus Polyculture in 2016




Epictetus Plant List - This year we have amended the plant combination slightly to allow more space for the plants. The following plants and cultivars will be grown in this polyculture in a 23 m x 1.2 m  raised bed.  



Lamiaceae - Epictetus
Dimensions - 23x1.2m
Area =27.6m2
QuantityRecount in JulyCropFamily Date Sown Date Planted
110Beetroot - Boltardy Amaranthaceae17/04/2017
71Dwarf Yellow Bean - "Rocquencourt"Fabaceae14/04/2017
35Kale - Borecole - 'Siberian' Brassicaceae28/03/2017
35Swiss Chard - 'Rainbow Mix' Amaranthaceae28/03/2017
220Parsnip White GemApiaceae07/04/2017