April 17

The biggest bang for your buck with bees (and other pollinators)

I have been looking a lot at lists of plants for bees and butterflies because I made myself a promise that this year I would add plants to the wildlife plot so that  there would at least one more that flowers each month.

So many people have lists and they each have different plants on them which I think suggests that actually it is quite site specific and what bees in one part of the country go for is not always the same across the country. Lists that I use are:

  • RHS – very good list of loads of plants classified according to when they flower. I am using the plants for gardens list but they also have a wildflower list and a plants of the world list. The wildflower list has plants for ponds so that will be useful. They also have three research papers based around Plants for Bugs – bees and other pollinators, plant-dwelling invertebrates and ground-active invertebrates with some interesting findings which I will talk about in a separate post.
  • The Wildlife Trust doesn’t have the biggest list but almost everything that is on it is in the wildlife garden – not surprising because the whole plot was set up by the Devon branch.
  • The Bumblebee Conservation Trust has plants divided into groups according to whether they are shade or sun-loving.
  • The Butterfly Conservation trust has a list of plants for butterflies, many of which are on the RHS list but also has a caterpillar food plant list.
  • Goulson Lab created by Dave Goulson, an expert on bees and other insects in the garden, has a list with stars for their desirability by pollinators.

Bang for your buck!

So, what has proved most popular on the Exmouth Hamilton Lane wildlife garden? In March and April, the plants that have had the most pollinators are:

Red-tailed bumble bee on Vinca major

Buff or white-tailed bumble bee on Symphytum ‘Hidcote Pink’.

Something unidentified yet on the grape hyacinth

 

 

 

 

 

 

 

  • Vinca major – this has been full of a range of bumble bees and other pollinators (Western bee-fly) and yet is not a plant on any of the lists!
  • Skimmia japonica – this plant hums with pollinators every time you walk past it and smells delicious
  • Symphytum ‘Hidcote Pink’ – this is a member of the comfrey family and drips with pollinators in both the sun and semi-shade. Again, this particular type of comfrey does not appear on the lists.
  • Grape hyacinths for pollinators other than bumble bees

 

April 4

Climate and weather

Module 5 of the online permaculture course is all about climate. It’s important because climate helps to refine a design. But how does it do this?

Knowledge of climate can help us:

  • choose the correct techniques, e.g. raised beds or beds dug into the soil that can be flooded
  • choose the right sort of plants and animals
  • choose the right sort of materials to use and whether we want to insulate or build in thermal mass, e.g. greenhouses in cold climates with insulating walls, the amount of ventilation needed in a house.

It is often said that Britain doesn’t have a climate, it has weather. Friends of mine from the centre of France only understood why the British were so interested in the weather when they lived here. In France where they lived, the weather was fairly consistent from day to day and over the seasons. In fact, the weather used to be set for day after day after day whereas here we can have rain, shine, snow and a storm all in one day.

So, what determines climate?  There are seven factors which affect climate: Latitude, ocean currents, elevation, topography, near by water, prevailing wind and vegetation.

Latitude

The nearer to the equator the the more sun  because the sun hits the equator more directly and in a more concentrated manor. The earth is tilted 23.5 degrees on its axis and this means that for half the year the north is tilted towards the sun and then away from the sun (and vice versa for the south) so the rays hit the earth at a different angle and intensity than they do at the equator. The latitude of the equator is 0° and for the Britain 50°  (Cornwall) to 60°  (Shetland Isles). Exmouth is 50.6°N.

Ocean currents

Ocean currents are a very important element for the climate of Britain. As a small island, in comparison with Europe, we are very affected by them. A line drawn from London around the globe would pass through southern Siberia and near Hudson Bay in Canada yet London is much milder in winter. The reason for this is the ocean current, specifically the Gulf Stream which brings warm water from the Caribbean.

Devon has the longest coastline of any region in the UK, having coastline on the north and south of the county.

Elevation

In general, for every 100m that you go up, the temperature drops by 1°. Air is less dense at altitude, the molecules are more dispersed than at sea level. As a result of this the molecules do not bump into each other so much and therefore produce less heat. In Exmouth we are at sea level so there is no reduction in the temperature due altitude.

Topography

Topography is how the geography of the place affects the weather and ultimately the climate. Hills or mountains can create rain and the weather can be different on the windward or leeward side. There can be a funneling of winds due to the shape of the land and a large body of water such as a lake or reservoir can also create milder temperatures.

The west of the UK is higher than the east through plate movements many, many years ago. The prevailing winds are south westerly and this means that there is a lot more rain in the west compared with the east. However, Exmouth is in the rain shadow of Dartmoor as evidenced by the comparison rainfall chart for Princetown on Dartmoor , windward side of the moor and Exmouth (leeward side of the moor). Our rainfall is about half or less of that in Princetown.

J F M A M J J A S
Princetown in mm 219 169 162 109 120 116 112 133 156
Exmouth in mm 88 69 62 63 64 61 59 67 60

We are in a temperate climate with cool, wet winters and warm, wet summers but that is not the same for the whole country. The south east is cold and dry in the winter and warm and dry in the summer. The north west has mild winters and cool summers with heavy rain all year round and the north east has cold winters and warm summers with steady rain all year.

The nearest place to Exmouth with a different climate is Gran Canaria which has a sub tropical climate with hot summers and mild winters and is a place many people from the UK visit in the winter.

The Koppen-Geiger Classification

This is a climate classification system based on the vegetation that grows in a place because plants depend on temperature and precipitation to grow. There are 5 climates – A. tropical, B. Dry, C. Temperate, D. Continental and E. Polar.  These are then divided into sub-categories according to level of precipitation and then the level of heat. The UK is Cfb which is temperate (or ocean), the f stands for no dry season and the b is the temperature of each of four warmest months 10 °C or above but warmest month less than 22 °C. Using maps based on this system from 1901 to 2010 it can be seen that there is an increase in aridity across the world and a decrease in polar regions.

The USDA hardiness zones are used world wide to denote the type of plants that will grow in that region. Most of the UK is zone 8 but here in Exmouth we are in zone 9 meaning that the lowest average temperature is -6.7°C.

The Royal Horticultural Society (RHS) has its own hardiness classification but applies it to plants rather than locations. It works on the theory that we all have microclimates in our gardens and therefore can place a wider range of plants than one overall rate of hardiness might suggest.