A big thank you to everyone who took part in the Plant Club BioBlitz! Over two weeks we made 725 observations of 313 species across the UK. We had observations from car parks in Portsmouth, pavements in Leeds and London, people’s gardens, and even clifftops in Cornwall and the Outer Hebrides. You can view all our observations on iNaturalist.

Plant Clubbers mostly photographed plants which were in flower, which is not surprisingly as this is when they are most noticeable and easiest to identify. There were fewer photographs of grasses, rushes, sedges, ferns and horsetails, and very few bryophytes – mosses and liverworts. I was surprised to see not many trees observed, are they overlooked as plants?
Why record plants?
Plants are the basis of all habitats and ecosystems so understanding changes in their habits and distribution can help us monitor and understand how the Anthropocene is affecting plants and what needs to be done. Here are some examples:
Changing seasons
Phenology is the study of the timing of animal and plant life cycles, including plant flowering time. Recording the time of year plants flower over many years can help monitor how seasons are changing due to climate change. Between 2015 – 2016 volunteers on the Natural History Museum Orchid Observers project used historical specimens and new photographs to understand how climate change is affecting orchid flowering times.
Monitoring invasive species
Many UK plants were introduced by people, either deliberately as crop or garden plants, or accidentally. Most don’t do any harm, but some have a negative impact on other organisms, environments or on people, these are known as invasive species. Our Plant Club BioBlitz participants observed some invasive species, including Himalayan balsam (Impatiens glandulifera) and Montbretia (Crocosmia pottsii x aurea) – these observations help monitor the spread of invasive plants.
Changes in plant populations
Recording plant species can help scientists understand the effects of human activities on plants, including climate change, pollution and changes in land management. The species most observed during the Plant Club BioBlitz is a good example:
Top five species from the BioBlitz
1. Stinging nettle (Urtica dioica)

Often unpopular due to its painful sting and vigorous growth, nettles grow best where there are lots of nutrients and have been increasing and out-competing other plants as a result of nitrogen pollution from fertilisers and vehicle exhaust. It’s not all bad news – the stinging nettle supports over 40 different insects in the UK, including some of our most loved butterflies. They are useful for people too; the young leaves are edible, and the stems can be made into an eco-friendly fabric.
2. Wood avens (Geum urbanum)

This is a plant of semi-shady woods and hedgerows but often appears in gardens and urban areas too. Although it is sometimes considered a weed by gardeners its yellow flowers are attractive to insects. The fruit are burrs with long hooked spines that tangle in the fur of animals (and people’s socks!) which allows the plant to disperse to new areas.
3. Common ragwort (Jacobaea vulgaris)

Ragwort is poisonous to grazing livestock, particularly when dried in hay but it’s a valuable plant for wildlife and if you are not near grazing land there is no need to remove it. In the UK, around 150 species of insect have been recorded feeding on ragwort. Many butterflies, hoverflies and other pollinators feed on the pollen and nectar of the flowers. Ragwort leaves are the main food of the stripy caterpillars of the cinnabar moth, one of the UK’s most colourful and distinctive moths.
4. Bramble (Rubus fruticosus complex)

This is another plant people have a love-and-hate relationship with! It’s thorny branches and tendency to quickly outgrow other plants can make it unpopular with gardeners but it also produces delicious blackberries. Going blackberry picking with my family was one of the highlights of childhood summer holidays and we would make them into pies and crumbles as well as just eating them with a little sugar. You might be surprised to learn that there is not just one bramble species – it is a species complex (or aggregate) of around 350 microspecies, perhaps explaining some of the variation in how good the blackberries taste! Experts in brambles are called batologists.
5. Herb robert (Geranium robertianum)

Like wood avens this is a plant of semi-shady woods and hedgerows which also grows well in disturbed places such as gardens and urban areas. One of its most characteristic features is its strongly scented leaves which many people find unpleasant, giving it an alternative common name of stinking bob! The small pink flowers are attractive to insects and it often has red stems, especially when growing in sunny places.
Keep looking for plants
If you enjoyed the Plant Club Virtual BioBlitz there are plenty of opportunities to continue learning to identify and record plants:
- Take part in the Great British Wildflower Hunt during spring and summer
- Record ‘weeds’ in your garden with the Garden Wildflower Hunt
- See if there is a square that needs monitoring for the National Plant Monitoring Scheme (NPMS) – you don’t have to be an expert.
Look out for our next event on our BioBlitz webpage. What nature activities would you like to take part in at future virtual BioBlitzes? If you have ideas, please email Victoria Burton, Interim Project Coordinator.
Great write-up and thank you for organising this!
The reason I often don’t record trees on iNaturalist is that I can’t tell whether they were cultivated or are wild, which is one of the things it asks.
Thanks Camilla that’s really useful to know! I must admit I didn’t record any trees myself, other than the little ash seedling in my garden. That’s even though I walked under them while recording little pavement plants – I’m not sure why that was.