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Gardening & Horticulture

Gardening & Horticulture

Gardening and Horticulture

Read out Gardening and Horticulture Blog

One of the very first and most frustrating things that I learnt as a tutor was how little difference there is between the best assignments and those that only scrape a pass. Often the difference is as simple as one assignment using world class sources and another one just getting by with a few webpages. I’ve recently signed up for an online course here at ADL, training me for the RHS Level 2 diploma in horticulture exams, and I’m determined to track down the best resources available!


In this post I wanted to share some of the books I’ve found the most useful, and ask if anyone had any extra suggestions for me:



Humans have an uncanny and incredible capacity to attribute meaning to pretty much anything and teach that meaning to others. This ability to create a language from ordinary items and symbols allowed the Victorians from the upper stratas of society, who were taught expressing certain things by word improper, to make grand, intense declarations of love, hate, friendship or indifference via bouquets of flowers and herbs.


It was not proper, nor polite, to declare social war on another in speech. But it was perfectly acceptable to do so via a bouquet of Tansies. Could one tell the handsome gentleman one met at that dance they...


So far in this series we have looked at the pesticides used today, the pesticides banned since World War II, and the first industrial chemical pesticides. In this final post, I want to tell a less well-known story: how pest control functioned before the modern period, especially in medieval and early modern Europe. Chemical pesticides were one of the least relevant aspects of pest control in this period, so this post will also describe physical, cultural and biological pest control. Although the pest control methods used in this period were unreliable and unscientific by today’s standards, they still have some interesting lessons...

In previous posts, I told the story of today’s controversial pesticides, and then went back to describe the pesticides famously banned since World War II like DDT, dieldrin, the organophosphates and the neonics. In this post, I’m going to describe how the first modern European pesticides were discovered, marketed and produced on an industrial scale. This is the story of sulphur, copper and (chillingly) arsenic.


Of the three big chemicals sulphur (American English ‘sulfur’) was perhaps the first to be recognised and used regularly (Zadoks, 2013; Frank and Conover, 2015). It was, arguably, the first reliable pesticide of Europe. It...

Pesticides, herbicides and fungicides (generally considered together as ‘pesticides’ or informally as ‘chemicals’) have a long and controversial history.On the one hand, we need them to keep towns and streets pest-free to 21st century standards, and they also have an often-overlooked, vital environmental function in protecting our National Parks from invasive species like Rhododendron.On the other hand, over the last five hundred years they have also caused significant damage to the health of humans, wildlife and ecosystems. This is the first of a series of posts in which I’m going to take a more historical view of pesticides. I’m going...

It’s official! After only one year of online study at the Academy for Distance Learning, I have just received my certificate from the RHS. I’ve passed all eight modules and I now hold the Level 2 Certificate in the Principles of Horticulture!


The RHS Level 2 qualification is the most recognised certification in the industry, and it’s the mark of a professional gardener. Even elite employers like the National Trust start their job adverts with “RHS Level 2 or equivalent”.

It usually takes a year full time or two years part time to study for the Level 2 Certificate in the Principles of Horticulture, so I’ve managed it in very...

Note - we strongly recommend this be read in conjunction with articles titled 'Self and Cross Pollination' and 'The Importance of Pollination for Top Crop and Fruit Breeders'

An F1 hybrid is the first filial ( F1) generation produced by crossing two pure bred parent plants.

What is a Pure Bred Plant?

Pure bred parent plants are ones which have been selected by getting rid of any variations, anomalies or sudden mutations until the population is uniform. A population is required with as little genetic variation as possible. This may take several generations and very careful control as the breeder does not want pollinators...

Rhododendron is a very popular genus of shrubs for gardens due to its clusters of flowers, which can cover the surface of the shrub, most often in spring. They are generally evergreen (except the deciduous Azaleas) and the individual flowers are concave (tubular, funnel, trumpet or saucer shaped) with long filaments (unlike flatter Hydrangeas). They tend to only grow well in acidic soils and will change colour depending on the pH. At least 500 species from across four continents have been cultivated, and thousands of cultivars have been bred (Brickell, 1996, p. 868). The first known cultivated Rhododendron species was Rhododendron...


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Disclaimer: Every attempt is made to ensure all information from the academy is accurate and that the student has attained the competencies taught in a course, at the point of their assessment. Beyond this point, the graduate is responsible to maintain their acquired competencies, and apply acquired knowledge and skills in a way which is appropriate to the unique characteristics of each application. This will release the academy from any liability, action and claims of whatsoever nature in connection with, or arising from any such information, instruction or advice, given by any student or ex-student, whether directions given during the course are followed or not.