The Polyculture Market Garden Study — Results from Year 5–2019

Paul Alfrey
15 min readDec 18, 2019

Here are the results from the fifth and final year of our Market Garden Polyculture Study. This study looks at the differences between growing annual vegetables and herbs in polycultures vs growing them in traditional blocks. Although this was the final year of this study, we are just getting started and next year we will be continuing our polyculture study focusing on the productivity of perennial forest gardens and biodiversity within the gardens. Registration for next year’s study is now open and you can find out more about that here.

Permaculture Internship/Training/Research

During this post you will find an overview of the trial garden and the polycultures we are growing, a description of what we record and the results from the 2019 trial. You can find results from previous seasons here and I’ll be publishing a summary of the results from the full 5 year study in the near future.

First of all we’d like to say a huge thank you to the 2019 crew that joined us for the study this season and that make it possible for us to carry out our experiments and research.

Ronan Delente — Michael Krack — Leonie Steinherr — Ben Peirson — Lilly Clark — Martin Votava — Amy Brangwyn — Eileen Wylicil — Tobi and Christina.Ruchel — Karo Castro-Wunsch — Kiki Ami — Maria Cruz — Shahara Khaleque — Jolanda de Rooij — Paul Vdsande — Simon Leupi — Eva Goldmann — Ryan Sapsed — Rowan Brooks — Joana de Melo Sampaio — Ezekiel Orba — Ranjetha Vijayakumar — Chris Kirby Lambert — Peter AlfreyMihaela TzarchinskaPhilip Varionov — Lea Valfigueira

Thank you all for your valuable input, it was our pleasure to host you and we look forward to seeing you again some day.

Here’s a photo album from the season and you can find a week by week diary of the season here

The Polyculture study crew of 2019 :)

Garden Overview

Location: Bulgaria, Shipka
​Climate: Temperate
Köppen Climate Classification — Dfc borderline Cfb
USDA Hardiness Zone: 5b — 7a
Latitude: 42°
Elevation: 565 m
Average Annual Rainfall: 588.5 mm
Prevailing Wind: NW & NE
Garden Name: Aponia — Polyculture Market Garden

The six longer beds in the left hand corner of the photo on the right (the Aceaes) are the trial beds, the focus of this study.You can find the location of the Polyculture Market Garden on google maps here (labelled as Aponia on our Project map)

Garden area: 256.8 m2
Cultivated beds area: 165.6 m2
Paths: 50 cm wide — 91.2 m2
Bed Dimensions — 23 m x 1.2 m Area — 27.6 m2 per bed
Number of beds: 6

Study Area Path and Bed Layout

The beds are named after common vegetable families in order to familiarise participants with the use of Latin and introduce them to some major plants families. The bed names do not correspond to what is planted in the beds.

The Polycultures

We experiment with many polycultures and have developed a categorization system for ease of reference. They are categorized by life cycle i.e annual, perennial or combi (annuals and perennials) and further categorized by function. i.e support, infrastructure or production. Often a polyculture will provide multiple functions, but the primary function is what sets them to each category. I give all our polycultures nicknames. For example, all polycultures in the annual and production category are named after Stoic Philosophers.

The study is based on a polyculture I call Zeno an annual/production polyculture. As we are looking to see how polycultures compare to conventional growing we also include a control for the Zeno polyculture i.e. the same crops from Zeno but planted in a more conventional block pattern. In the below illustration you can see the planting plan of the trial beds.

We scaled down to one bed of each polyculture and one bed of control for Zeno this year as opposed to two of each as seen above. We have extrapolated from the data we recorded from each bed to keep the results comparable to the previous years where we were growing on 4 beds.

Polyculture Zeno

We’ve been growing Zeno in the garden for around 11 years now. It’s been very successful in our home gardens and in 2015 we scaled it up for the market garden.

Photos from Zeno PolycultureFor more info on plant spacing, management and maintenance of this polyculture see a previous post here.

Zeno Plant List — The following plants and cultivars were used in this polyculture;

Tomato — Solanum lycopersicum ‘Tigerella’
Tomato — Solanum lycopersicum ‘Ukranian purple’
Tomato — Solanum lycopersicum ‘Yellow Pear’
Tomato — Solanum lycopersicum ‘Chocolate Pear’
Tomato — Solanum lycopersicum ‘Alicante’

French Beans — Phaseolus vulgaris ‘Cobra’
French Beans — Phaseolus vulgaris — Local
Courgette — Cucurbita pepo ‘Black Beauty’
White Bush Scallop — Cucurbita pepo
Squash — Cucurbita pepo ‘Waltham Butternut’
Basil — Ocimum basilcium ‘Sweet Genovese’
Pot Marigold — Calendula officinalis

Zeno Planting Scheme

Zeno — Vegetable and herb polyculture/guild 6.5 m section of planting scheme

Zeno Control

The control includes all of the above plants but planted in blocks along the bed (see below). We want to see how the two planting schemes compare, i.e. whether or not the polyculture will produce more and the difference in the amount of time needed to cultivate the different layouts. The fertility inputs for both beds are the same.

What we Record — Inputs

Time Input — We record how long it takes to develop, maintain and manage the garden. The time is recorded for each task starting from sowing the seeds, preparing the beds, planting and caring for the plants, harvesting, preparing for market and packing away. The time taken for each task is rounded up or down to nearest minute. Nearly all of the records are based on 2 people carrying out each task unless otherwise stated in the record sheet.

Fertility Inputs — All fertility additives are recorded including; seed sowing mediums, composts, mulch, and ash.

Ash being applied to the beds in early April at an approx. rate of 100 -120 g per m length (a Fiskar Hand Trowel full per m length of bed)

Financial Inputs — Costs — The costs associated with the garden are recorded. We do not cost the time spent on the garden but do provide estimates of the time the activities take. Set up and tool costs were included in the first year records. This year we only recorded operating costs.

N.B. We eliminate many costs by growing our own plants from seed, making composts and sowing mediums, growing summer and autumn mulch and saving seeds. We also provide our own support stakes from trees grown on site for the crops.

Seedling Beds

What we Record — Outputs

Crop Yields — All produce is weighed directly after harvest. The produce is recorded into two categories, fit for market and fit for processing.

Polyculture Yields

Financial output — Profit — The market value of the produce is estimated based on the average prices we were receiving from local buyers, veggie boxes and Trustika buyers club in Sofia.

N.B. We do not sell all of the produce from the garden. Some of the produce is consumed by the team or preserved.

What we Record — Surveys

Soil Analysis — Each spring and autumn we obtain a soil sample and send it to NAAS of the Ministry of Agriculture and Food. To take a sample we take approx. a hand trowel full of the top 20 cm of soil from 8 random areas from the beds, mix it together and send 400 g “bagged and tagged” to the lab the same day.

Physical Analysis — Each spring the team carry out a series of 9 tests that are designed to provide an indication of soil health based on observable physical properties of the soil. It’s a soil management tool developed by farmers for farmers to track the developing health of soils. We have slightly modified the test for our purposes.

Regenerative Landscape Design Course participants working through the soil health test cards

Invertebrate Survey — Entomologist Chris Kirby-Lambert has been carrying out invertebrate surveys in the gardens for the last few years but unfortunately we did not have the funds available to complete this project. You can find his Outline of Invertebrate Diversity Monitoring Project here. We did start a new biodiversity study this year and I’ll be posting our method and results from this survey in the coming weeks.

A sample of invertebrates from the gardens- Photos by Chris Kirby-Lambert

Pest and Disease — Thanks to Victoria Bezhitashvili, who joined us for the study in 2018, we have a general record of some of the common pests and diseases in the garden . You can find Victoria’s observations here.

Results

We’ll start off by looking at the results from the soil analysis and soil health tests, then look at the results for each polyculture and finally finish up with the overall garden results.

Soil Results — Mineral Analysis

Each spring and autumn we take soil samples and send them to NAAS of the Ministry of Agriculture and Food. The sample is taken before we add any fertility in March at the beginning of the season.

The first sample taken in March 2015 in the table below is the base sample taken before work in the garden began.

For better presentations of the below tables click this link

Sample Location — Aceaes2019Nitrogen mg/kgPhosphorous — Potassium mg/100gApril (before adding compost)pH (KCI)N03NNH4NP205K206.829.420.259.926.42018Nitrogen mg/kgPhosphorous — Potassium mg/100gMarch (before adding compost)pH (KCI)N03NNH4NP205K206.749.535.3130222017Nitrogen mg/kgPhosphorous — Potassium mg/100gMarch (before adding compost)pH (KCI)N03NNH4NP205K206.7325.14.8514739.62016Nitrogen mg/kgPhosphorous — Potassium mg/100gMarch (before adding compost)pH (KCI)N03NNH4NP205K206.654.435.798825.2November (after final harvest)pH (KCI)N03NNH4NP205K206.618.173.8344.122.12015March (before adding compost)pH (KCI)N03NNH4NP205K205.6915.42.8916.313November (after final harvest)pH (KCI)N03NNH4NP205K206.4416.24.4543.914.4

Soil Results — Soil Health Card

This year’s soil health card test scored 72.2 — an increase from last year’s test of 65.6. The highest score obtainable for this test is 88.

You can find the full results from 2015–2018 in the spreadsheet 2019 Annual Polyculture Market Garden Study — Published Records — Sheet 6.Soil Test Cards

Should you wish to use this soil card you can download the Soil Health Card forms with instructions on how to carry out the tests here.

Inputs and Outputs — Zeno

The amount of time spent on Zeno was 46 hrs

For better presentations of the below tables click this link

TaskTime in minsSet up404Planting /Sowing327Garden Care585Irrigation105Harvesting300Propagation151.5Fertility12Mowing270Market Prep600Analysis5Total hrs46 hrs

The fertility inputs on Zeno were as follows:

Fertility Inputs
ItemTotal QuantityStrawbales31Compost for
Tomatoes (L)32.6 LSeedling Mix
for Squash (L)10.4 LSeedling mix for Beans (L)13.2 LWood Ash kg6.72 kgMulch — Lawn Mower Clipping (L)540 L

The yield outputs for Zeno totalled 198 kg of produce — 3.59 kg per m2.

CropWeight in gTomatoes20640Tomatoes — (Processing)1770Beans33140Courgette42425Tomato (projected)Basil995Total197.94 kg

Inputs and Outputs — Zeno Control

The amount of time spent on Zeno Control was 42 hrs and 50 mins.

For better presentations of the below tables click this link

TaskTime in minsSet up378Planting /Sowing231Garden Care520Irrigation105Harvesting300Propagation151.5Fertility12Mowing270Market Prep600Analysis5Total hrs42 hrs 50 mins

The fertility inputs on Zeno control were as follows:

Fertility Inputs
ItemTotal QuantityStrawbales31Compost s (L)32.6 LSeedling Mix
for Squash (L)10.4 LSeedling mix for Beans (L)13.2 LWood Ash kg6.72 kgMulch — Lawn Mower Clipping (L)540 L

The yield outputs for Zeno totalled 168 kg of produce — 3.04 kg per m2.

CropWeight in gTomatoes11895Tomatoes — (Processing)2450Beans23770Courgette41880Tomato (projected)Basil3895Total167.78 kg

Zeno Polyculture vs the Control

This year’s results show the polyculture outperforming the control in yield by approx 24 kg and taking approx. 7 hrs and 30 minutes longer to manage.

This year’s results

ZenoControlTotal time46 hrs42 hrs 50 minTotal Produce197.94 kg167.78 kg

Last year’s results

ZenoControlTotal time36 hrs 5 min35 hrs 20 minTotal Produce237.23 kg191.57 kg

You can find the above results in the spreadsheet 2019 Annual Polyculture Market Garden Study — Published Records — Sheet 9. Inputs and Outputs per Trial. For date stamped harvest records for Zeno see here.

Inputs and Outputs — All Beds

Aponia — The Polyculture Market Garden

The amount of time spent in total was 88 hrs 50 mins

CategoryTotal timeFertility24Analysis10Set up782Market Prep1200Mowing540Planting /Sowing558Garden Care1105Irrigation210Harvesting600Propagation303Total time spent5332 min

Chart showing % of time allocated to each task

Category Description

  • Garden Care includes weeding, tying and pinching out tomatoes, replacing weak plants, inspecting plants
  • Propagation — includes sowing seeds, watering seedlings, pricking out seedlings
  • Market Prep — includes packing produce for market
  • Harvesting — picking produce from garden
  • Irrigation — applying water to crops after transplanting and during the high summer
  • Mowing — Mowing the pathways and applying the trimmings to the surface of the bed
  • Planting — Planting crops into beds and sowing crops directly into the bed
  • Fertility — Applying additives (in this case wood ash)to the soil following soil analysis results
  • Set up — Preparing beds , forking over , mulching, adding compost, erecting supports and removing supports

The total fertility inputs for all beds

Fertility Inputs
ItemTotal QuantityStraw Bales62Compost (L)65.2 LSeedling Mix
for Squash (L)20.8 LSeedling mix for Beans (L)26.4 LWood Ash kg13.44 kgMulch — Lawn Mower Clipping (L)1080 L

Some shots of the market garden

Results in Summary

The garden produced 365 kg of produce from a cultivated area of 110 m2.

The time spent on the garden was 88 hrs from sowing the first seeds indoors in February to packing up in late October.

The fertility inputs of the garden were 63 Straw bales, 1205 L of compost. 20 kg of wood ash, 224 L of sowing medium, 1620 L of lawn clippings.

Here’s a photo album from the season and you can find a week by week diary of the season here

Comments on Results

Time Input

  • Not included in the records were other tasks carried out around the site such as making compost, harvesting stakes and support sticks, establishing beneficial habitat such as wildlife ponds, hedgerows/stick piles.
  • The time for preparing the produce for market i.e quality control, packaging and delivery, was estimated at 2 hrs per week.

Financial Inputs — Costs

  • Not included here are the set up costs for the garden. These costs were included in the first years results. The costs recorded here are the annual operating costs which is basically the cost of seed, and fuel,oil and maintenance for the lawn mower.

Financial Output — Income

  • A polyculture market garden should have a polyculture of revenue. Our study currently focuses on annual vegetable production. We chose to begin our study of annual vegetables as it is the most accessible practice to most people requiring the least amount of investment making it ideal for a novice or curious grower. Next year we begin to look closer at perennial polycultures trails in our new gardens. You can find out more about these trials here
Perennial Polyculture Trials in Ataraxia

Other potential revenue from the Polyculture Market Garden includes perennial crops, plant nursery, adding value to produce and courses and training. We plan to add a record of these activities to represent better the financial potential of a Polyculture Market Garden.

Considerations :-

  • We aim to grow equal numbers of the same cultivar in the polyculture and the control but this year our courgette and tomato cultivars were not distributed equally.
  • Due to the warm autumn and lack of frost Tomato — Solanum lycopersicum ‘Currant Sweet Pea’ that we planted last year made an appearance in the autumn with a nice crop of fruits from 5–6 plants that had self sown. The yield from these are not included in the records

N.B. We took base times for the majority of tasks carried out in the gardens in the first two years of the study. These tasks were carried out by a volunteer team that had little or no prior experience in horticulture. An experienced grower or with repeated experience of these cultivation methods should be able to reduce the task times significantly.

You can access the full spreadsheet here that includes all of the data entries and task descriptions. (note there are multiple sheets that can be accessed from the blue tabs running along the top of the sheet).

If you appreciate our work please consider making a donation and help us expand our research dedicated to permaculture and regenerative practices. find out more here.

Why are we doing this research?

If you are reading this you’re most probably aware of the environmental damage caused by industrial agricultural practices. We believe this damage is unnecessary, and aim to provide healthier models of food production that yield nutritious affordable food while at the same time promoting biodiversity and general ecosystem health.

Polyculture gardens providing food for humans and other organisms

Industrial methods are heavily researched and funded, and there is a general belief among many farmers and growers that this is the only practical way of operating. Following 12 years of cultivating polyculture gardens we are seeing that small scale biologically cultivated polyculture gardens are a realistic and practical way of providing food for humans whilst preserving biodiversity and general health in the environment. Furthermore, we believe this type of agriculture can help create thriving local economies that strengthen community, provide dignified work and enhance the amenity value of an area.

Little data exists showing the productive capacity of polyculture systems and the economic viability of them. I believe there is a need to fill this gap and provide data and concise coherent models that can be replicated easily. This project intends to go some of the way to achieve that.

We aim to address the following questions;

  • How productive can polycultures be?
  • What advantages can polycultures provide ?
  • How much time do polyculture gardens take to establish and manage?
  • How economically viable are these gardens?
  • How bio-diverse can our food producing systems be?
  • Can we provide clean, nutritious, affordable food whilst enhancing biodiversity?

I make no claim that polyculture can feed the world but I do claim with 100% conviction that anyone can grow polycultures and by doing so they are taking a small but significant step in reversing at least a small portion of the damage that industrial agriculture creates.

Want to get involved? Sharing, Feedback and Collaboration

We have our record keeping spreadsheets available on Google sheets and Excel. These sheets include all of the data entries and task descriptions (note there are multiple sheets that can be accessed from the blue tabs running along the top of the sheet). If you would like to keep your own records or replicate our trial we’d be happy to give you a copy of the spreadsheet, just drop us an email or leave a comment below with your contact details and we will send it over to you.

If you have any suggestions and feedback on how you think we could improve the study or you have heard about or practice similar studies on other guild/polycultures we’d love to hear from you.

Upcoming Courses

If you would like to create a forest garden and gain some practical hands on experience come and join us in the Spring. We’ll be covering site surveying, landscape design software, installing access, beds, irrigation channels, planting tree, shrub, herb and ground layers and wildlife ponds. All in 3 days! And plenty of follow up material to take away with you to digest slowly.

Design and Build — Forest Garden Course — Regenerative Landscape Design Course

Registration for our April 2020 course is now open with 15% discount on accommodation and food fees when you register as a group (2 or more).

If you appreciate the work we are doing you can show your support in several ways.

Polyculture — Forest Gardens — Permaculture — Regenerative Design Webinars

Want to join us for one of our live webinars? Forthcoming webinars include ;

How to Select Fruit and Nut Trees for your Forest Garden/Polyculture Orchard — Webinar

Everything you need to know about Nitrogen Fixing Plants

Polyculture — Forest Gardens — Permaculture — Regenerative Design Webinars

Would you like to be involved in the project? We are currently offering 1–6 month positions on our polyculture study.

Permaculture and Regenerative Design Internships

We offer a diversity of plants and seeds for permaculture and forest gardens including a range of fruit and nut cultivars. We Deliver all over Europe from Nov — March.

We also offer a range of products all year round from our Online Store

Give a happy plant a happy home :)

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