Soil Temperature and Seed Germination

A few days ago we sowed the tomato seeds for this season's market and home garden. It never ceases to amaze me what little indoor space you need to rear thousands of seedlings. We use two 50 cm x 30 cm x 15 cm trays to germinate approx 150 seedlings from 10 cultivars. When they get bigger we move them into two 1.3 x 8 m beds covered with polythene to rear them before they take their permanent positions in the gardens in early - mid April.

Many of the plants we grow I prefer to sow directly outside and one of the most important things to consider when sowing is that the temperature of the soil is high enough for the seed to germinate.

Other important considerations include:

• whether the seed requires any pre-treatment before it will germinate, i.e stratification and scarification (mainly relevant for perennial plants particularly trees and shrubs).
• how deep you sow the seed - too shallow is better than too deep. 
• that the correct moisture levels are kept constant during the germination phase - not too wet, not too dry and with the ideal moisture levels similar to that of a wrung out cloth.

Elaeagnus commutata -  Epigeal germination 

This post we'll focus on soil temperature for germinating seeds. We'll look at why this is important, how to take soil temperature, and I've included a table showing the minimum and preferred soil temperatures for germination of some common plants.

Eruca sativa - Rocket germinating 

Often you will find a monthly guide on a seed pack indicating when to sow seeds and this generally works okay, but can be misleading. If you have a long cold winter and the soil is cold, germination will be delayed and in some cases the seeds may rot in the ground.  On the other hand, if the soil is unusually warm in the spring, it's possible to seed earlier. Being able to tell the soil temperature and being aware of the preferences of each plant will result in more or your seeds germinating.

Tomato seedlings

Measuring Soil Temperature

You want to measure the temperature at seeding depth and this will differ for each seed you sow. The general rule is sow to a depth of no more than twice the diameter of the seed, but like I said above it's better to go too shallow than too deep.

Any thermometer that will measure temperature at a specific depth can be used to measure soil temperature. Insert the thermometer into the area where the seeds will be sown and wait a few minutes before you take a reading.

Bear in mind that each area of your garden will probably have a different temperature. The soil temperature is influenced by the following factors:

• Bare soil warms much faster than mulched soil and vegetated soil.
• Dry soil will be warmer than wet soils.
• South facing soils will be warmer than north facing, and the amount of shade cast on the soil will affect the temperature considerably. 

Gingko biloba seedling 

Warming up the Soil

As the air temperature starts to warm up in early spring you may like to get a head start with your sowing and accelerate the warming of the soil. If you have a mulch on your soil for the winter you can temporarily remove the mulch. The dark coloured soil will absorb all wavelengths of light and convert them into heat, warming the soil much faster. Another alternative is to leave the mulch on and cover the bed with a plastic sheet or glass pane. On a sunny day this will provide considerable heat. Of course you can also remove the mulch and use the sheet or glass on the bare soil and this has the added benefit of germinating any seeds in the patch that can be pulled before you start sowing.


Here's a table providing the minimum and preferred soil temperature for a number of crop seeds and the estimated time it takes the seeds to germinate

 Minimum and Preferred Temperatures for Common Crops

Basil Seedlings

Upcoming Courses

If you would like to create a forest garden and gain some practical hands on experience come and join us this Autumn. 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.

Registration for our October 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.

• Make a purchase of plants or seeds from our Bionursery

• Consider joining us on for one our Regenerative landscape design training course

• Donate directly to our Polyculture Project crowdfunding campaign. 

• Comment, like and share our content on social media.

Polyculture/Regenerative Landscape Design Webinars 

This season we are running live interactive sessions hosted on Zoom on a range of topics. You can register for a  webinar here.

Polyculture/Regenerative Landscape 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 :) 

The Bionursery

References 

http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex1203
http://www.rodalesorganiclife.com/garden/plant-seeds-right-depth

Trees for Bees

Trees are the bee's knees, and I'm pretty fond of bees too :)

Trees are an important, stable source of food for bees and other pollinators providing thousands of flower heads all in one place.

I could go on and list their other virtues but the fact you're on my blog leads me to assume that  you already have a pretty good appreciation of both trees and bees so let's get straight to the point of this post and find out which trees attract bees.

Bees from our Garden

The good news is there are trees that provide nectar and pollen for bees pretty much all year round. Better news is that most of them are very easy to grow and suitable for growing in a wide range of conditions including small and large gardens and in the wild.

I've put together five lists of trees that you'll find below;

1. Trees for Bees that also provide fruit or nuts 
2. Nitrogen Fixing Trees for Bees 
3. Ornamental Trees for Bees   
4. Master list including all of the above in alphabetical order (including USDA hardiness for each species)
5. Master list including all of the above in order that trees flower 

Indicated on the lists are when the trees are in flower, what they offer the bees, i.e pollen, nectar or honey dew (see below for honey dew description), and whether and when the trees offer fruits, nuts or other wildlife foods. I've also included a link to plant profiles of trees that we stock in our bio nursery. You can find details of a bee tree multi pack below that we are offering from the nursery this spring.  

Trees for Bees that also provide fruit or nuts

Nitrogen Fixing Trees for Bees

Ornamental Trees for Bees  

Master list including all of the above in alphabetical order

Master list including all of the above in order that the trees flower 

It's no coincidence that flowering and bee activity are triggered by warming temperature, During long cold winters in locations at high altitude or regions of high latitude, plants will not follow the sequence as illustrated below. In our gardens at approx. 580 m above sea level on the 42nd parallel north, the below table is an accurate representation, although there is a lot of variation within the month.

If you know of a tree or shrub that is great for bees and is not on the above lists please share it in the comments section below. Also if you see any mistakes in the list, I'd really appreciate it if you could let me know also in the comments section below.

Honey Dew 

If you have ever parked your car under a tree and arrived back to find it covered in a sticky substance, you have come across honey dew. You have the sap-sucking psyllids or aphids to thank for this.

An aphid feeds by inserting its straw-like mouthpart (proboscis) into the cells of a plant and draws up the plant’s juices or sap. Most aphids seem to take in from the plant sap more sugar than they can assimilate and excrete a sweet syrup, honey dew, that is passed out of the anus.

For many other insects including ants, wasps, and of course the bees, this is a valuable source of food. Ants harvest it directly from the aphids, bees generally collect it from where it falls.

Ant drinking "Honey Dew" - I could not find the original source of this photo to give credit

Check out our previous blog here where I profile a polyculture design dedicated to bees and other pollinators 

Polyculture for Pollination Support 

Upcoming Courses

If you would like to create a forest garden and gain some practical hands on experience come and join us this Autumn. 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.

Registration for our October 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.

• Make a purchase of plants or seeds from our Bionursery

• Consider joining us on for one our Regenerative landscape design training course

• Donate directly to our Polyculture Project crowdfunding campaign. 

• Comment, like and share our content on social media.

Polyculture/Regenerative Landscape Design Webinars 

This season we are running live interactive sessions hosted on Zoom on a range of topics. You can register for a  webinar here.

Polyculture/Regenerative Landscape 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 :) 

The Bionursery

http://www.urbanbees.co.uk/trees/trees.htm
http://www.bbka.org.uk/files/library/bbka_trees_for_bees_3-way_1306864371.pdf

A unique learning opportunity studying the productivity of polyculture market gardens in the beautiful Balkans.

Encouraged by high yields and high levels of biodiversity that we have been recording in our home gardens we have extended our research to look at how we can provide nutritious affordable food whilst enhancing biodiversity in polyculture market gardens. We are delighted to be offering a unique opportunity to take part in this study. Would you like to join us?

What are we doing ?

We are undertaking a multi year study of market gardening growing herbs, vegetables and perennial fruit and nut polycultures. The study aims to compare our polyculture plots with conventional organic plots, record levels of biodiversity in the gardens and look at set up and running costs (in terms of finances and time) and outputs in terms of produce and income.

Diversity of high quality biologically produced food from our polyculture gardens 

The approach we take to market gardening goes way beyond "organic". We design biological systems that rely on the native ecology to function as opposed to external manufactured inputs, and as a result our gardens service not only our needs but the needs of other organisms too.

click here to view our results so far 

Permaculture/Polyculture Market Garden @Balkan Ecology Project

What will you be doing ?

You'll be working closely as a team producing food from the market garden for yourself, local markets, and a food co-operative and will be recording all aspects of the process including how long it takes to develop, maintain and manage the associated costs, the fertility requirements, the returns in produce weight and income derived from the sale of the produce.

Our Polyculture Market Garden - photo by Huma

Spring 2017 we will also begin development of a new experimental garden growing perennial polycultures providing fruits, nuts, vegetables, biomass, timber and wildlife habitat. We'll install a gravity fed irrigation system, wildlife/irrigation ponds, living fences of native species, several habitat features for current species on site, and 6 trial beds that will house 4 perennial polycultures, designed to be highly productive and wildlife enhancing.

Perennial Polycuture Trial Garden

​
Click here for the Garden location (labelled as  East Side Trial Garden on our Project map)

We are planning to record all aspects of the project including observed levels of invertebrate diversity, weather data and soil analysis. We’ll be looking closely at inputs i.e set up/running costs, fertility/water requirements and time, and outputs i.e produce, income, soil fertility and invertebrate diversity.

The aim of the trials is to test the ecological and economical viability of growing these polycultures in market gardens and farms in order to meet the following needs/wants:

• production of high quality, high value food 
• cash crops from secondary/ tertiary polyculture partner species
• improvement of soil fertility
• provision of biomass for use as mulch
• timber supply for use as vegetable supports and larger round wood material for farm infrastructure
• enhanced levels of biodiversity

Some of the resident wildlife from our permaculture market garden. 

Click here for month by month activities.

Why should you take part ?

​This is an excellent opportunity if you are considering starting a garden and/or are interested in ways to provide affordable healthy food whilst increasing biodiversity.

As a participant of this study -

• You will gain valuable insight into what it takes to actually run a market garden. As well as the practical skills you will develop, we'll dedicate time each week to covering essential theory including site design and implementation, plant propagation, polyculture management, basic botany, record keeping, harvesting, irrigation, marketing and advertising, and budgeting/financial planning. 
• Enrollment to the 6 month program entitles you to participate in courses and training events that take place during the program. 
• You will be contributing to an area of research where little information exists i.e the productivity of polycultures and associated biodiversity dynamics. 
• This study will be published online and freely available to all for future reference and you will be credited accordingly.
• You will be spending time in a truly unique area of the world, working as part of a dynamic team of fellow enthusiasts in an inspiring environment.

2015 team in the gardens  

Where will you be?

The project is based in the town of Shipka, Bulgaria on the foothills of the Central Balkan mountain range in the Rose Valley. It's an area of high biodiversity, beautiful countryside and historical sites of global, cultural and scientific significance. The project site is located on an abandoned piece of agricultural land on the western outskirts of the town that we call the Paulownia Garden. See Map for Paulownia Garden Location.

Shipka Town - home to Balkan Ecology Project 

You'll also be learning from our existing garden, a 10 year old residential property with a highly productive and well established forest garden composed of over 400 species of plants. Our central garden is a good example of small scale intensive ecological design and includes examples of rainwater harvesting, grey water reed beds, wildlife ponds, multiple composting facilities and hosts a small plant nursery. We practice various methods of biological vegetable production including guild planting and crop rotation, and rear pigs, chickens and rabbits from this property.

The Home Garden

How to take part?

The study will run from April 1st - September 30th. Ideally you will be able to commit to the project for the full duration of time. We are also willing to accept applications for shorter periods of time if you feel passionate about joining the project but cannot dedicate 6 months.

The contribution for joining the study for the full 6 month period ( April 1st - September 30th) is €650. This includes rent and bills for the whole period and admission to all courses and events held during those dates.

If you would like to participate for less than the full 6 months the fee is €150 per month, including rent and bills.

Once we have received your registration we will contact you and arrange a Skype meeting to talk through the process and answer any questions that may arise.

Following this, if you decide you would like to take part, the fee for the duration of your stay should be paid in full to secure your place. Payment can be made via PayPal (processing fees apply ) or bank transfer in £,€ or BGN.

Accommodation

Our self catering volunteer house is basic but comfortable in a beautiful location at the edge of Shipka and around 15 - 20 minutes walk away from the project site. The house has Wi-Fi internet, a shared kitchen and bathrooms and a garden. ​

The Volunteer House -  a view from the east 

Fruits and vegetables produced from the gardens are available to you from June onwards, and quality products such as eggs, milk, cheese, honey and meat can be purchased from local producers. The cost of living is relatively low here and estimates of living costs based on the experience of previous participants is between €90 - €120 per month.

There is plenty to do around Shipka and our location is perfect for exploring. The wild coasts of the Black and Adriatic Sea are just a few hours away, extensive trails deep into the Balkan mountains start from your doorstep. Istanbul, Bucharest and Thessaloniki are a bus ride away and there are great day trips includng Koprinka Lake, Kalofer waterfalls, Buzludja and Etara living Museum to name but a few.

Why are we undertaking this study ?

Industrial agricultural practices often result in destruction of habitat for many organisms. We believe this is unnecessary, and want to provide healthier models of agriculture that can provide nutritious affordable food while at the same time promoting biodiversity and general ecosystem health.

Industrial methods are heavily researched and funded, and there is a general belief among many farmers 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 in the environment. Furthermore we believe this type of agriculture can help create thriving local economies that strengthen community and enhance the amenity value of an area.

Little data exists showing the productive capacity of polyculture systems and the economic viability of them. There is a big need to fill this gap and provide solid data and concise coherent models that can be replicated easily and provide real solutions to the environmental damage caused by industrial agriculture. This project intends to go some of the way in filling this gap.

Registration is now open. Register here.

Here's what previous year's participants said!

Last years polyculture study team 

"Taking part in the Polyculture Study was a life-changing and inspiring time for me. I learned loads about permaculture, about Bulgaria and to reconnect with the simple things in life. On top of that Paul, Sophie and their kids are awesome people! I'd recommend this to anyone wanting to learn more about permaculture, experiencing rural life or just thinking of a change of career and lifestyle!" - Ute Villavicencio

"I took part in the 2016 Polyculture Market Garden Study with the Balkan Ecology Project. I started without much knowledge of gardening at all, but the hands-on work at the study sites, alongside the weekly theory lessons, helped me build an understanding of permaculture principles. By putting these into practice, I learnt how to create a productive polyculture market garden, and how to apply sustainable, eco-friendly design to a plot of land.
I also had time to complete an online Introduction to Permaculture course, travel to other Bulgarian towns on weekends, walk in the mountains and work in the home garden. Paul, Sophie and the boys are wonderfully warm, supportive and knowledgeable hosts, the study team were fantastic and Shipka is a very special place. I highly recommend getting involved! " - Marika Wanklyn

" Being a part of the Polyculture Study was a very special period of my life. I realized how inspiring it is to be in touch with soil and plants, and creatures inhabiting the garden I worked in, and also to be in good touch with the people I worked with. I am happy to have had this opportunity to support the Study and the wonderful family behind it, and to be supported by them in return." Anna Boncheva

Upcoming Courses

If you would like to create a forest garden and gain some practical hands on experience come and join us this Autumn. 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.

Registration for our October 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.

• Make a purchase of plants or seeds from our Bionursery

• Consider joining us on for one our Regenerative landscape design training course

• Donate directly to our Polyculture Project crowdfunding campaign. 

• Comment, like and share our content on social media.

Polyculture/Regenerative Landscape Design Webinars 

This season we are running live interactive sessions hosted on Zoom on a range of topics. You can register for a  webinar here.

Polyculture/Regenerative Landscape 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 :) 

The Bionursery