Wednesday 5 March 2014

Nectar Point Networks 2

In a previous post (15 Jan 2014), I introduced the concept of a Nectar Point Network (NPN). The driving force for the establishment of NPN hubs in the Cardiff area is Professor Denis Bellamy, who is the Chairman of the Conservation Management System Consortium (CMSC) and a former head of the Zoology Department at University College Cardiff. He has put together an informative website on NPNs (see link below). The Cardiff NPN is taking shape through a ‘bottom up’ approach. In an email in February, Prof Bellamy explained that, “it is envisaged that each hub organises itself as a self-sustaining community nectar point with its own action plan and local funding”.

The Nightingale Community Garden in Dinas Powys was established last year, a process I outlined in a series of posts (see links below).  At the start of this year, I registered the Community Garden as a potential Nectar Point Network hub. As a first step into making this happen, I applied for and got an award (£100 of garden vouchers) from Keep Wales Tidy’s Wild Weekend Voucher Application, which this year aims to improve food sources for pollinators and is aimed at community groups. One stipulation is that plants purchased should be on the Royal Horticultural Society (RHS) Perfect for Pollinators Plant List.


I spent the voucher on two bee nesting boxes; five large pots; four bags of peat-free organic compost; a bee-friendly Escallonia ‘Apple blossom’ bush; and packets of nectar-rich plant seed, including lavender, foxglove, borage, cornflower, marigold, marjoram and 'wild flower honey bee mix'.  I intend to add a winter-flowering honeysuckle at a later date, along with  some surplus rosemary, primrose and heather from my garden. The idea is to establish a border of nectar-rich plants at one end of Nightingale Community Garden, with five pots of bee-friendly flowers in other areas of the garden. This will be our starting point, from which other activities will flow.


There are numerous nectar-rich plants that can be grown for pollinating insects. The consensus is that variety is more important than focusing on any one plant species. This is for several reasons. A range of different species can be grown that produce nectar at different times of the year, for instance, to feed pollinating insects active in different seasons. Furthermore, different pollinators are adapted to different flower structures, for example, long-faced bumblebees with long feeding parts (e.g. Bombus hortorum) are specialised to get the nectar from flowers with long corolla, such as foxgloves. Another factor is flower colour, with different pollinating insects homing in on different colours (e.g. Bombus  lapidarius has a fondness for yellow flowers); so the more colourful the pollinator border the better!

A recent study, conducted by Mikhail Garbuzov and Francis Ratnieks at the University of Sussex with 32 popular summer flowering plants over a two-year period, identified which were the most attractive to insect pollinators. Borage (Borago officinalis), lavender (Lavandula) and marjoram (Origanum majorana) scored highly. However, not all lavenders were attractive to bees, only the wild types, with highly-bred ones such as those with novel colours not proving very attractive. Borage flowers were the most attractive to honey bees. Perennial lamb’s ear (Stachys byzantina) was the most popular plant with more unusual bees, such as the solitary wool-carder bee (Anthidium manicatum).  The authors concluded that choosing the plants you grow carefully can make a big difference to pollinators. The least attractive plant in this study was the widely-planted pelargonium.

A previous study, conducted at the University of Cambridge in 1999, of 24 plant species (not the same plants as in the Sussex study) also revealed large differences in terms of insect pollinator visits. The most visited plants by honey bees in this study were Malva moschata, Salvia pratensis, Malva sylvestris, Scabiosa columbaria, Centaurea pratensis, Knautia arvensis, Trifolium repens, Salvia verbenaca, Lythrum salicaria and Saponaria officinalis.   The bumblebee most recorded was Bombus pascuorum, which preferred Trifolium pratense, Salvia pratense, Trifolium repens, Laminium album and Stachys sylvatica.

The references to both these papers are below. They provide a good entry point into the scientific literature on this subject.

I will post more on NPNs and pollinating insects later in the spring, along with an update on progress in the Nightingale Community Garden as it enters its second year.

Nectar Point Network website:
https://www.sites.google.com/site/nectarpointnetwork/

Previous post on Nectar Point Networks:
http://sfnottingham.blogspot.co.uk/2014/01/nectar-point-networks.html

Previous posts on Nightingale Community Garden:
Sept 2013
http://sfnottingham.blogspot.co.uk/2013/09/creating-community-garden-10.html
June 2013
http://sfnottingham.blogspot.co.uk/2013/06/creating-community-garden-9.html
April 2013
http://sfnottingham.blogspot.co.uk/2013/04/creating-community-garden-8.html
March 2013
http://sfnottingham.blogspot.co.uk/2013/03/creating-community-garden-7.html
Feb 2013
http://sfnottingham.blogspot.co.uk/2013/02/creating-community-garden-6.html
Jan 2013
http://sfnottingham.blogspot.co.uk/2013/01/creating-community-garden-5.html
Oct 2012
http://sfnottingham.blogspot.co.uk/2012/10/creating-community-garden-4.html
Aug 2012
http://sfnottingham.blogspot.co.uk/2012/08/creating-community-garden-3.html
Feb 2012
http://sfnottingham.blogspot.co.uk/2012/02/creating-community-garden-2.html
Jan 2012
http://sfnottingham.blogspot.com/2012/01/creating-community-garden.html

References:
Livio Comba, Sarah A. Corbet, Lynn Hunt & Ben Warren (1999), Flowers, nectar and insect visits: Evaluating British plant species for pollinator-friendly gardens’, Annals of Botany 83: 369-383. Online: http://aob.oxfordjournals.org/content/83/4/369.full.pdf

Mikhail Garbuzov & Francis L.W. Ratnieks (2013), Quantifying variation among garden plants in attractiveness to bees and other  flower-visiting insects’, Functional Ecology (Oct 2013): http://onlinelibrary.wiley.com/doi/10.1111/1365-2435.12178/full