Gardening for Insects

Some thoughts on pollinators and their plants

I wrote in a previous post about the effect of climate change on insects. In this issue, I'm sharing some thoughts about how we can help insects in our gardens.

Yesterday, I was invited to chat about pollinators with a local gardening group. We met up at the Grove Community Garden in Edinburgh's Harrison Park and looked for insects, with a particular focus on pollinators. Yesterday’s weather was dull, intermittently rainy and very windy, not ideal for finding insects. The photo below shows the garden in June, on a day when the weather was sunny.

The group are keen to garden for wildlife and wanted to find out how they could help pollinators and other insects. Today's essay is based on what I shared with the group.

I've visited the garden before and seen a good number of bees of various species enjoying the variety of plants there. Due to the poor weather, we didn’t see many insects in the garden yesterday, and only one pollinator, a Common Carder Bee.

We walked from the garden to nearby North Merchiston Cemetery, where the only pollinators we saw were a few Speckled Wood butterflies and a tired looking Buff Tailed Bumblebee.

However, despite the weather, we all enjoyed the walk and learning about pollinators and other insects.

What are pollinators and why are they important?

Pollinators are insects (and sometimes other creatures) that carry pollen from one plant to another to help the plant to breed and therefore set fruit. Pollinating insects include: honey bees, other species of bees, hoverflies, beetles and butterflies.

Honey bees are important pollinators, but they compete with other pollinators for pollen. However, honey bees aren't native to the UK, they’re domesticated and can take over from native species, causing these species to decline. So, unless you want to produce your own honey, setting up a bee hive is not a great thing to do. Instead, focus on creating a good garden for wild bees and other native pollinators, by planting native, nectar rich species of flowers. For example, in the UK, good plants to attract bumblebees and other pollinators include: lavender; comfrey; Hypericum; scabious, thistles, vetches, heathers and umbellifers. You can help the pollinators further by planting:

• species that flower at different times of year, so that there’s always food for the insects;

• patches of the same plant species, as bees like to stick to one species while foraging; and

• flowers of different shapes to attract insects with differing mouthparts and feeding techniques.

Other useful insects

Some insects are helpful to gardeners because they keep down the numbers of pests. For example, ladybirds eat aphids, hoverflies and lacewings eat various pest insects and parasitic wasps can keep down the numbers of pests by parasitizing them (there is probably a parasitic wasp specific to every species of insect, including parasitic wasps themselves). Ground beetles eat slugs.

Many birds (including robins and blackbirds) and mammals (including hedgehogs) eat insects, so having a good insect population in the garden helps other animals.

Again, planting the right native plants will attract helpful insects. For example, ladybirds like chives, yarrow and thistles.

Other top tips for managing your garden to help insects

* don't use chemicals or peat

* create a log pile and / or bee hotel for the insects to live in

* make a compost heap

* create different habitats and leave part of the garden to grow wild

* create a hedge, good species to include for UK wildlife include: hawthorn; hazel and blackthorn

* leave dead-heading until late Spring, as many insects will hibernate in the flower heads

* don't cut back ivy until late Winter, as its fruits offer winter food for pollinators

* put coarse bark or sharp gravel round veg or flower beds to deter slugs and snails

Useful Links

Here’s some useful information from the UK charity Buglife about helping insects in your garden.

Here’s an excellent guide to helping insects from the UK's Wildlife Trusts.

You may also want to record the insects that visit your garden. This is an enjoyable activity that can give you an idea of how your garden is helping your local wildlife. You can find out more about wildlife recording in last week's post.

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Interesting Articles

A beautiful, heart-breaking memorial to lost glaciers on the Rice University website.

A fascinating article about plankton on the Guardian newspaper site.

Microplastics are infiltrating brain tissue, studies show: ‘There’s nowhere left untouched’ in another article from the Guardian.

Meet Sri Lanka's turtle guardians, also in the Guardian.