What is a Botanic Garden?

Tropical zone pool
Tropical zone pool

When I’m out and about outside work, and people ask what I do, and I tell them I work in a Botanic Garden, the most common next question is, what IS a Botanic Garden? I answer my stock response, a museum with living exhibits, but this reply just scratches the surface of what a Botanic Garden really is in the 21st century.

The more accurate answer to this question is that a Botanic Garden is many things, we are at our core a living museum, a curated collection of significant species; but surrounding this core are layers that create a life and vibrancy, each as important as each other. (more…)

Curator’s live tour 1/7/20

Here is the latest live tour in the Garden which took place on 1st July; Nick discusses pollination including the evolutionary adaptations of flower colour and shape, the native grassland and the importance of knapweed and yellow rattle, and the plants of the Mediterranean Maquis.

We apologise for the low sound quality in this video, but there should be enough to enjoy the tour!

The hows, whys and wheres of composting…

By Alida Robey

I have had some intriguing responses to my previous post on composting– most commonly “Hurry up and tell us how to do it!” ; so without further delay, I give you the why, where and (most importantly) how of composting….

Why compost?

There is so much more to composting than simply meeting our own personal needs.  For me, the global urgency is such that I would have us label all shop bought fruit and veg: WARNING: Not composting will lead to the depletion of our soils! Here’s why:

Compost helps regenerate soils and improve soil structure

Current agricultural practices suck nutrient out of the soil. The resultant produce has less nutritious value than in previous generations, [1] meaning we are needing to eat more to get the same nutritional benefits. [2] Commercial fertilisers are designed to promote maximum growth, not necessarily superior nutrient content of the fruit and vegetables produced. Nor do these fertilisers benefit  soil structure and health. The fibre of compost added to soil helps improve water retention and also helps moderate temperature extremes.

It provides a slow release of nutrients (especially nitrogen)

Unlike synthetic fertilisers, compost adds a bank of biological activity to the soil, which encourages beneficial worms and helps to make significant quantities of nutrients (such as nitrogen, phosphorous and potassium) bio-available slowly over time.

Composting keeps organic waste out of the landfill

About a third of household waste is likely to be kitchen-generated organic matter. Composting it yourself reduces increases in your council tax by saving some of the huge costs of domestic waste collection transport and disposal. Also, organic matter in landfill produces methane (a greenhouse gas  that contributes to global warming) and nitrogen-rich leachate (pollutes rivers and streams).

Composting transforms plant material, food waste and other organic matter into humus or compost, which is a richly nutritious soil-like material with the added benefit of microorganisms that help plants take up  the goodness in the soil. In other words, it turns otherwise smelly, unwanted waste into something really productive and pleasant to handle.

Where to compost

A community composting bin in the Shelton Community
Garden in Shelton Stoke-on-Trent, Staffordshire.
Photo credit: Joshua Whiton via Wikimedia Commons

The traditional means of composting is a bin, a heap or an enclosure in a sunny spot in the corner of a garden.  However, you can do some very effective composting even without a garden of your own:
Community composting bins require one or two people to maintain but can receive compostable materials from a community. The compost can then be used for community gardens or by individuals in the community . They can be located in parks, communal gardens, unused corners, on the edge of school grounds and other public/semi-public spaces. 
Wormeries are a wonderful alternative for those in apartments or with limited external space.  A wormery is usually a small stack of trays, which is home to a colony of compost – eating worms (NOT earthworms) that will convert most kitchen waste into wonderfully nutritious ‘worm wee’ and worm castings that can be used to feed indoor or outdoor plants or given away to friends and neighbours to use on theirs.

How to compost

This is what I consider to be the basics.  Once you have tried some of this and found it’s not going as badly as you had imagined, then I suggest you access some of the online information that will help improve your productivity. 

What goes in?

IN: 
Veg peelings & fruit
Coffee grounds, tea bags, egg shells – crushed by a crunch of your hand
Cardboard (torn up no larger than a standard envelope), tissues, loo roll tubes & waste paper – shredded or scrunched up.
Especially welcome are egg boxes (ripped up a bit) and the contents of  paper shredders
Grass-cuttings (so long as you haven’t used weed-killer) and discarded pot plant contents including old compost and dead flowers
Plant prunings – chopped up to help decomposition
Weeds –  so long as they are not in seed, otherwise you will have them sprouting merrily back in the soil.
OUT (of compost bins but IN for wormeries)
Pasta, rice, couscous
Beans, pulses, lentils, cereals
Bread, chapatis, biscuits etc
Plate scrapings
Cheese and dairy products
Meat, fish and bones
Cooked potatoes
The reason many of the items above are excluded from compost bins but not wormeries is their attraction for vermin.
OUT (of everything)
Nappies
Cat and dog poo from animals that have been wormed.

Location, location, location

A typical compost available from
local councils.

For general composting, find a warm sheltered corner preferably reasonably accessible so you are not put off taking stuff there.  Set up your means of containing your compost, a compost bin or bins is the easiest, but a boxed-in area or even just a pile will do.  Your local council may, like Bristol, sell plastic compost bins and deliver them, all for as little as £12-15. You need to bear in mind that you will need to be able to turn the contents occasionally and that worms need access from below.

The great compost bake-off

Underlying the composting process is the chemical transformation of carbon materials (shredded paper, straw, vacuum cleaner dust, leaves, egg boxes, egg shells) and nitrogen materials (grass clippings of untreated grass, weeds, kitchen scraps, coffee grounds) into a whole new product – compost.  It is a bit like baking a cake where the ingredients are deliciously transformed by mixing and baking.  We can control the conditions in our compost to encourage the materials to decompose faster and effectively (i.e. to produce a really good cake rather than a baked lump of goo).
The other factors your composting recipe needs to include are a mix of particle sizes that assist aeration and hold enough (but not too much) moisture.  As with the cake, the mixing and aerating are important success factors between it just working and it being great. If it’s getting smelly, add more carbon materials and aerate it more frequently by turning it over.
Depending on your method, the transformation process can take just a few months.


Layer dress

Start layering your contents, bearing in mind the need to mix carbon and nitrogen items (roughly 2 carbon:1 nitrogen, but adjust according to whether it seems to look and smell healthy).  And just keep adding, remembering that it will all break down a lot smaller. I prefer to have 2 or 3 bins, and empty them out completely from time to time, retrieving the made compost from the bottom and piling the rest back into one bin. This can be a lot easier than turning the contents of individual bins. You can keep one bin of nearly decomposed compost at the ready for when you want to use it in the garden.
Happy composting!

Further resources about composting:

References:

[1] World Economic Forum (14 Dec 2012) What if the World’s Soil Runs Out? Time 

Undergraduates get their first glimpse at the garden

By Alida Robey

I’ve been promising myself a visit to the University of Bristol Botanic Garden since I arrived in Bristol four years ago. Life has intervened. Yet when the opportunity came to join the new intake of students from the University on their first practical of their 3 year undergraduate degree, I leapt at the chance. 
Once there, the thrill of the plants, garden, stories and mysteries within, were hard to resist!  I joined the briefing given by the Garden’s curator, Nick Wray, as he introduced the day’s second group of 70 students (over 250 students attended the practical over two days) to their PhD student demonstrators – there to inspire the undergraduates about different aspects of the gardens.  

An introduction to the day

These biology and zoology students were visiting the garden as part of their ‘Diversity of Life’ module – taking a first-hand look at some of the adaptations that have enabled plants to diversify into the more than 400,000 species that exist today. Beyond this, however, the practical offers an opportunity for the students to get to know each other and learn to work collaboratively, gain confidence in sharing knowledge,  as well as orientate themselves to this incredible resource available to them.
Nick and the demonstrators were up against time and the logistics of manoeuvring 70 students around 6 ‘work stations’. Students were split into manageable groups and two volunteer guides were brought in to assist moving the groups swiftly through the rotation of topics presented around the garden.
Off we went. As a newcomer myself, I shared the sense of wonderment and awe one student expressed as she exclaimed at how much more there was at the Garden than she had expected. She pointed out how interestingly organised the gardens were, which effectively revealed the story of plant evolution – a set-up that Nick had explained was unique to the University of Bristol Botanic Garden.

Into the glasshouses for plants that eat and are eaten

I followed a group into the glasshouses where Edith showed us the adaptations plants have evolved to cope with extreme habitats. Plants from very different families share common features that are adaptive in similar conditions. Euphorbia, for example, which grows in the deserts of Africa is so similar to the form of cacti found in the deserts of America that they are often misidentified – this is an example of convergent evolution.
The striking Haemanthus coccineus – a native of South Africa -flowers and then sets seed in autumn to coincide with the first rains, giving the seedlings a full rainy season to develop. The leaves appear well after the flowers to reduce the amount of moisture lost prior to the rains. Edith pointed out carnivorous plants that have adapted to nutrient poor habitats. She showed us a plant that produces citronella to deter insects and a species that looked half eaten to make it less attractive to herbivores.
The group was then passed along to Nick who ushered us into the tropical greenhouse to reveal further wonders, such as the orchids of Mexico that require pollination by moths to produce vanilla pods. When commercially produced in the Comoros Islands, pollination is done by hand for every flower – a task often given to children in this struggling economy. We saw the giant lily pads of Victoria cruziana. Reminiscent of triffids, Nick pointed out that in summer they have to be cut back every three days to prevent them growing out of the pond.
Nick Wray shows the students the largest seed in the world.
Photo credit: Nicola Temple

Hmmm… time to escape back into the fresh air where things were growing at a more manageable pace for me, but Nick continued to show the group other commercially important plants, such as lotus, bananas and cotton. He held up a specimen of the world’s largest seed – that of the sea coconut or coco de mer (Lodoicea maldivica), which can weigh up to 30 kg.

The students were then taken into an area of the glasshouses that’s not open to the public and shown some very rare and unique plants, including Amborella trichopoda, which is of particular interest because molecular analyses suggest this is one of the earliest flowering plants. It is the last remaining species of a group that first appeared on Earth more than 140 million years ago, when dinosaurs still dominated the animal kingdom.  A sprawling shrub native to New Caledonia, Amborelladoesn’t cope with changes in humidity very well, so it is kept behind plastic to control the humidity.
Some students scribbled madly, while others just chose to listen as Nick enthusiastically explained what a unique experience this is for University of Bristol students.  ‘Until last year, Bristol was the only botanic garden in the UK growing this plant,’ said Nick. (The University of Cambridge has recently acquired one.)

New Zealand garden – survival of the species

In the New Zealand garden, Dave showed the radical ways plants survive difficult conditions; in this case, the attentions of the now extinct Moa bird. This was graphically illustrated by Pseudopanax, which starts off its first 10 years or so as a sapling with hard, spiky, downward facing sword-like leaves. Once considerably taller – namely beyond the reach of 3m tall Moas – the trees don’t invest as much energy into being unpalatable and transform into an unrecognisably different form, with soft and safely inaccessible leaves reaching to the light.

Angiosperm phylogeny explained

A group gathers around the pond to learn about angiosperm
phylogeny. Photo credit: Nicola Temple

I moved on to hear about angiosperm phylogeny; a new term for me, but more exciting and less daunting than it sounds. In the past, plants were classified into family groupings based on their physical characteristics. With the advent of DNA sequencing in the last 20 years, we can use genetic relatedness to help us understand how plants have evolved. James, our demonstrator, pointed out some of the oldest species of flowering plants, including star anise (Illicium verum). This area of the garden is organised into the two major groups of flowering plants monocotyledons (seed has single embryonic leaf) and dicotyledons (seed with two embryonic leaves). The monocots include plants such as orchids and grasses, including agriculturally important species such as rice, wheat, barley and sugar cane. The more familiar garden plants, shrubs and trees, and broad-leafed flowering plants such as magnolias, roses, geraniums, and hollyhocks are dicots.

Learning in the garden beats a textbook any day

Speaking with the students, they said they enjoyed being able to touch and feel the actual plants, make comparisons and learn within this physical context. They could see as James explained how even though Protea, lotus, Banksia and London plane tree (Platanus x acerifolia) looked very different, their DNA suggests they are more closely related than they appear. Genetic relatedness is traditionally illustrated using a cladogram – a branching tree with scientific names at the end of the branches, with no sense of what these species look like. What an opportunity to see what the diversity at the end of those branches can look like!
Students use pens to see how flowers are
adapted to distribute pollen on the
pollinators that visit them.
Photo credit: Nicola Temple

My time ran out before I could get as far as the sessions on pollination and plant evolution!  With my head spinning from this intensive and whistle-stop tour of some of the delights and extraordinary features of this garden, I sat on a bench in the autumn sunlight to reflect on the afternoon with fellow blogger, Nicola Temple, who had invited me take part in this day.

Like many of the students I spoke with as we went from location to location, I was delighted to have had the opportunity to understand the great thought behind the layout of the gardens.  There was far and away more here than I had bargained on.  I wanted to keep going but knew I could only take in so much on my first visit.  As we had gone around I had been surprised as an observer to note how quiet the students were, very few asking any questions.  Having stood back from it though I wonder if, like me, they were overwhelmed by the hidden depths to this exceptional garden. I’m certainly going to seek every opportunity to spend more time here, whether learning or simply enjoying the peaceful and stunning surroundings.
And I daresay I will come across many of the students from this day, pursuing their studies and enjoying the sheer delight and boundless wonderment that nature continues to shower upon us and that this garden so beautifully illustrates.