Plants for Bugs

Plants for Bugs: Comma butterfly on Verbena bonariensis
A comma on non-native Verbena bonariensis in my garden this week - it was there for over an hour 

In May 2012 I wrote in my Secret Wisley entry:

"... I was taken on a tour of one of the Plants for Bugs trials sites: it was so fascinating I'm saving the details for another post."

How time flies... I've kept some secrets for a little longer than planned. Tucked away in a not-so-much-visited corner of Wisley I saw this:

View of part of the Plants for Bugs trials plot at RHS Wisley May 2012
Part of the Plants for Bugs trials area at RHS Wisley, May 2012

The RHS released the first news of their research results last week, so at last it's time to tell you more. The key message for gardeners here in the UK is:

 "Don't get too hung up on keeping to solely native plants; choose from a wider planting palette - particularly species from the northern hemisphere - to encourage more insects and other invertebrates into your garden."

From the thousands of invertebrates collected during the study, around 300 different species were identified. The research also showed pollinators may not choose native plants as their first-choice to visit. In addition, growing a wide mix of plants originating from around the globe extends the season of availability of important food sources such as nectar and pollen.

I think there's further good news for UK gardeners because


  1. Our choice of native plants is relatively small - approximately 1,400 species, with around a further 1,300 classed as naturalised (source: JNCC). Our gardens wouldn't be half as interesting if we stuck to just our native flora.
  2. Invertebrates are towards the bottom of the food chain, so if their population is a healthy one it's good news for the other wildlife that visits our gardens to feast on a tasty snack or three.
  3. I grow a broad mix of plants from many countries, so my garden's wildlife population has a better chance of being diverse and in balance. There is less chance of any pest - such as aphids - having a population explosion which in turn overwhelms my plants.
Plants for Bugs planting plan for a native species plot
A planting plan for a native plants trials plot - other plots had solely non-native (northern hemisphere in origin)
 or exotic (southern hemisphere in origin) plants

I had a think about the native and non-native plants in my garden after my Wisley visit, and I guessed correctly what the result might be. Many of the wildlife-friendly plants which sprang to my mind don't hail from these shores e.g. Buddleja aka butterfly bush. However, it's good to see the science has proved my notion, and it's interesting to note there's a difference in the results with plants chosen from the northern and southern hemispheres.

I've enjoyed watching the many invertebrate visitors to my garden this year and I'm planning on showing you some of them in a later post. I've seen quite a few insects for the first time - I think my woolly lawn might have helped...

Neatly labelled plots - it was a very cold spring in 2012, hence the lack of colour.
We were told that growth was about 3 weeks behind the norm at the time of our visit.

Note: the results may not be transferable elsewhere


Veg Plotting's non-UK readers - particularly from across the pond - may question these results as gardeners in the USA are often actively encouraged to focus on native species *. This is largely in response to:

  • Some non-native plants which are proving to be invasive e.g. the garlic mustard I wrote about for June's Blooms Day. 
  • Gardeners are also encouraged to provide the right habitat and native plants for key species like the monarch butterfly along its migratory path.

Whilst our definition of native is probably similar - plants which have arrived and established in a country without the intervention of man - our timeframes are different. In the UK we usually mean plants which were here at the end of the ice age 10,000 years ago, whilst in the States it's much later, at around the time of Columbus. 

The total number of plants native to the USA is more than ten times greater than the UK's at nearly 19,000, though these numbers are probably reduced at State level, owing to the variation in plant hardiness zones across the country. It means Stateside gardeners already enjoy a wider mix of plants to choose from within their native flora.

* it's probably the wide availability of support materials and articles aimed at USA gardeners online which has helped persuade some of us in the UK that focusing on native plants is better for our gardening too. That's why research such as Plants for Bugs is important as it helps us make better informed decisions.

The main Plants for Bugs information board at RHS Wisley
The main information board at the research area, showing the layout and some of the collection methods

Note: this isn't the complete picture


Gail's left a great comment about the importance of trees in our garden mix. For example, our native oak hosts hundreds of insect species, and that's just for starters. The Plants for Bugs study focused mainly on perennials and grasses, plus a few shrubs. I wonder what the results would be if our native trees, shrubs and other plants such as bulbs were compared with their non-native cousins.

However, I'm not suggesting we all start growing oak trees in our gardens as they're too large for most plots. A study of the smaller garden-worthy trees would be helpful and I'm a huge advocate of growing at least one tree in every garden. The RHS has a couple of lists of suggestions for trees and shrubs for your consideration: Trees for smaller gardens, and Trees and shrubs: native to the UK. 

My friend Gail's blog, Clay and Limestone is worth a read and note she hosts Wildflower Wednesday every fourth Wednesday in the month. It's a celebration of all wildflowers from around the world.

And then... there are other factors to consider, such as:

  • Single vs double flowers and how plant breeding for showier, often double blooms may affect the availability and accessibility of nectar and pollen. 
  • The specific plants insects like the holly blue butterfly need to complete their lifecycle.
  • The influence of factors such as habitat, height above sea level, aspect, soil etc. - these variables would have to be eliminated as far as possible in the RHS's study so the full impact of the 3 plant types they looked at could be compared. However, as a gardener I'm happy to vary the number of conditions (e.g. damp, dry, shady etc.) in order to grow a wider variety of plants and to attract more wildlife.

As with much of life, there aren't really any simple ways to ensure 100% success with gardening, but on balance I believe the key message from Plants for Bugs is a good starting point.

Further Reading


Links to the RHS's Plants for Bugs project:




Other reading which may be of interest:

The RHS's Perfect for Pollinators page has links to 3 PDF lists to help us choose the best nectar and pollen-rich plants for our gardens. I wrote a post a while ago on the bee-friendly plants I've found do particularly well in my garden. Since then, I've found Agastache, Knautia, Echinops and thyme are good for all kinds of insects in addition to the Verbena bonariensis shown at the top of this post.

It's great we can grow such a wide variety of plants, but that doesn't necessarily mean we should grow all of them. Here's Plantlife's guidance page on invasive non-native plants in the UK. NB some familiar plants such as Cotoneaster horizontalis are included.

Here's a list of invasive species I've found for the USA -  you'll see there's plenty on there which we welcome here, such as ox-eye daisy. Verbena bonariensis, the loved-by-many-a-UK-gardener-and-insect-alike plant shown at the top of this post is on the invasive watchlist for Washington State.

Comments

  1. Anonymous16 August 2015 at 15:32

    An interesting, and informative, post. Just about all the flowers I grow on the plot are with bugs in mind.
    Flighty xx

    ReplyDelete
    Replies
    1. VP16 August 2015 at 15:54

      Thanks Flighty - I keep it in mind for my plant choices too.

      Delete
  2. CJ16 August 2015 at 18:45

    A fascinating fact about verbena bonariensis, which I've grown for the first time this year. It's really interesting to learn that non-native plants are perfectly acceptable for insects. A most informative post, thank you.

    ReplyDelete
    Replies
    1. VP16 August 2015 at 20:07

      It's not just butterflies getting drunk on my Verbena boniariensis this year CJ, it's attracting all kinds of insect visitors which I can watch buzzing around the plants whilst I'm eating in our kitchen. It's a fabulous view. Not all non-natives are acceptable - as indeed applies to natives - it depends more on the whether they're simple flowers and the availability of the nectar etc. Then of course, there are those specialist cases where only one plant will do for a particular insect, which may be good for nothing for anything else. It's a more complicated picture, but at least we now know that planting a wide-variety of plants is a simple way of ensuring a good mixture of garden visitors :)

      Delete
  3. Gail16 August 2015 at 20:40

    Enjoyed the post ...a lot! I plant non-native to my eco-region plants (but native to Eastern Tennessee, the Central US and Southeastern US) and luckily for me these plants haven't proven invasive. I am thrilled that they attract pollinators and other invertebrate species. What I remind folks around here is don't forget trees, they're super host plants. gail

    ReplyDelete
    Replies
    1. VP17 August 2015 at 08:29

      Good point Gail, our native oak tree is host to hundreds of species. I wonder what a research project would find if native vs non-native trees would find. I'll update my post with this thought, thank you :-)

      Delete
    2. VP17 August 2015 at 08:38

      Thst should read... If native vs non-native trees were compared

      Delete
    3. Gail17 August 2015 at 12:34

      Thanks for the linklove and shout out about Wildflower Wednesday! xo

      Delete
    4. VP17 August 2015 at 12:36

      My pleasure Gail - I have a post-Fling entry for Wildflower Wednesday to write up sometime :)

      Delete
  4. VP17 August 2015 at 15:57

    I'm so glad I didn't post at the time... it would have been a 'hey this is really interesting and I loved my visit, but watch this space for the results' kinda post ;)

    ReplyDelete
  5. Sue Garrett18 August 2015 at 11:02

    I try to have different shapes and colours of flowers and also have as long a season as possible/

    Do they include cabbages, carrots etc.:)

    ReplyDelete
    Replies
    1. VP21 August 2015 at 16:38

      Hi Sue - no it was only herbaceous perennials. There's a link to the planting list in the resources at the end if you're interested.

      I'm amazed at what carrots and leeks attract when they're allowed to flower.

      Delete
  6. Beth at PlantPostings21 August 2015 at 21:21

    Very informative, Michelle. My garden has a mix of native and non-native plants--more non-natives near the house (anything that isn't invasive and that the rabbits don't like to eat), with more native plants the further one moves from the house. Many non-natives definitely have wildlife value, as long as they aren't invasive. I didn't realize the U.S. had so many more native plants than the U.K., but I suppose part of that is the geographic size of the country. Thanks for all the great info!

    ReplyDelete
    Replies
    1. VP22 August 2015 at 12:11

      You're welcome Beth :) Interesting point about the difference in size between our 2 countries, sometimes islands can be more diverse e.g The Gallapagos. For some reason it's not happened for us - perhaps factors such as climate and our proximity to the continent (or even our relatively recent isolation from the rest of Europe) come into play...

      Delete
  7. Stephanie 139a25 August 2015 at 09:42

    Interesting post - and I think the key message for me here is to grow the plants I love, which is great news :) #hdygg

    ReplyDelete
  8. Chickenruby25 August 2015 at 14:39

    We have similar experiments set up in both Dubai and South Africa and I saw bug tents in Canada when I visited last month

    ReplyDelete
    Replies
    1. VP26 August 2015 at 08:50

      Ooh that's interesting, do you know if any results have been published yet?

      You've reminded me one of my Twitter correspondents in Canada has given me some references to the research there, I must add them to this post.

      Delete
  9. Amanda26 August 2015 at 20:44

    Goodness me, this is very informative! I've always taken a "scatter and see" approach to gardening, so far the bugs seem to like my style!

    ReplyDelete
    Replies
    1. VP28 August 2015 at 08:56

      Thanks Amanda. I like the sound of your approach to gardening. W e can learn much from our own observations, which is a common theme here on this blog :-)

      Delete

Post a Comment

I love hearing from you and welcome thoughtful conversations :)

Comments aiming to link back and give credence to commercial websites will be composted!

Your essential reads

That blue flower: A spring spotter's guide

Image
Spring is a prime time for blue flowers and my daily walks currently have several from the same plant family* lining the local footpaths. As I walked past the Donkey Field the other day, I overheard some children ask their parents** what the pictured blue flower was. It reminded me it's often mistaken for those other familial blues and this time was no different, as they said it was forget-me-not, instead of the green alkanet it actually is. As well as similar flowers, most of these plants are hairy in their nature, flower around the same time, and favour damp, shady places. Many of them are great for pollinators too, especially bees and this week's warm weather has certainly drawn them to these flowers. This makes it even more likely for these plants to be mistaken for each other and it's a great opportunity for me to put together a spotter's guide in case you find the same flowers on your outings. Staying with green alkanet, the key features which set it ...
Read more

Jack Go To Bed At Noon

Image
Last year this rather exotic looking flower appeared on mine and several other allotments for the first time. Having been stumped (again) by Mr Allotment Warden as to its identity, I rushed home to find out what it was. It's salsify, aka the marvellous Jack Go To Bed At Noon - named as such because its flowers always close by midday. Here you can see both open and closed flowers - making it seem even more exotic and alien than in the first picture. I think this must be the cultivated version because the flower in my Francis Rose Wild Flower Key looks exactly the same in form, but is bright yellow in colour and called meadow salsify . Its other common name is Goatsbeard, which must be a nod to the fantastic dandelion-like clock which forms the seed head. With 'parachutes' like those shown above, who knows how far our plotted plants came from. I rather like the photographic dissection of the seedhead found in this link . Salsify is edible: its lateral shoots and fl...
Read more

Red Nose Day - Gardening Jokes Anyone?

Image
The nation goes ever so slightly bonkers on Red Nose Day - hurrah! Previously, it's been very easy to join in - usually via a dress down day at work plus lots of people up to mad things at the station and in the office. Everyone smiling for once - it's a real feel good day and all in a good cause. This year's different - every day's a dress down day for me now - my friend L suggested yesterday that perhaps I could have a dress up day instead and whilst that's a good idea, I confess that ballgowns and tiaras don't really feature in my wardrobe: scruffy student's always been my favourite look. So my Red Nose Day contribution for this year is to compile a list of gardening related jokes. For each one (clean ones only please) you leave in the comments below, I'll make a donation of 50p to the cause. Here's a few for starters just to get you warmed up: Q Why do potatoes make good detectives? A Because they keep their eyes peeled. Q What did the grape...
Read more

Salad Days: Mastering Lettuce

Image
I've decided one of my salad challenges for this year is to grow as many lettuce varieties as I can, ready for the publication of my planned Factsheet* later on. The idea is to grow as many of the Tried and Trusted lettuce varieties last year's Salad Challengers helped compile, then provide a visual guide and as many lettuce facts as I can muster. So far I've found around half of those listed**. Then naturally whilst I was out searching - because such is the way with seeds - a number of other varieties found their way home too ;) A couple of weeks ago I sowed 22 varieties***. Just the simple act of sowing them has me intrigued. Why are some lettuce seeds black and others white****? They split into about half white to half black in my sample and as far as I can tell it's nothing to do with whether they're a type of cos, iceberg, or whatever. I sowed them indoors and popped them into a propagator on the windowsill. The soil's too cold outside for sowing ...
Read more

VPs VIPs: Derry Watkins of Special Plants

Image
Last week I had the pleasure of visiting Derry Watkins at her home, garden and nursery - the acclaimed Special Plants - just a few miles along the road from me. I first met Derry at one of her open garden days last year and was keen to find out more about her wonderful garden and running an independent nursery. She specialises in tender perennials and regularly goes on plant hunting trips to find new treasures, particularly in South Africa. As well as running Special Plants and opening her garden under the NGS scheme , Derry holds day courses at her nursery, hosts Special Tuesdays from April until September, lectures and has written a couple of books. How did you find your way from Connecticut to the UK? I'd started a biodynamic vegetable garden in Connecticut and we used to have people come along at weekends to help out. A particular young man turned up: he returned many times and at the end of the summer I married him. So it was all down to love? Isn't that the...
Read more

#mygardenrightnow: heading into summer with the Chelsea Fringe

Image
Ahhhhhh, that's better! I love walking through dewy grass in bare feet, not that there's much in the way of grass on my back lawn this weekend. My wild and woolly lawn has morphed into meadow of sorts this month, which even NAH admits looks attractive*. It's also proved a great source for my Flowers for mum project so far, yielding self-sown perennial cornflowers, lamb's ears, and lemon balm in addition to the blooms you can see. These originated from elsewhere in the garden, the ox-eye daisies must have blown in from the A350 nearby. * = he got very stroppy about the weeds aka self-sown foxgloves in the lawn one year, so he's come along a bit since then. Skimble's demanding to say hello to you too. He does enjoy the patio when it warms up. If the embedded video doesn't work try this link instead. The Nectaroscordum are a revelation. I planted the bulbs around 2 years ago, but it's only this year they've bloomed properly. The bee...
Read more

Make Use of Mildew

Image
On my garden patrol this morning I spotted some powdery mildew on a couple of my new Verbena bonariensis plants. I suppose it was almost inevitable as I prefer to grow my plants hard - this means no water for them unless they look absolutely desperate. This approach means plants root themselves more deeply and have a better chance of survival during spells of dry weather like we've had lately. However, it also means I run the risk of problems like today's, especially with any garden newbies planted late in the season. We've had a good drop of rain overnight, so this should help my plants survive. I'll mulch them later today to help lock in the moisture as it's water stress which encourages the mildew to take hold. I've also removed the infected leaves and sprayed the rest with a milky drink.* I'm also pleased to find there's a use for my infected leaves. Oliver Ellingham at Reading University has started a PhD - sponsored by the RHS - researchi...
Read more

The Resilient Garden

Image
  Part of Tom Massey's Resilient Garden at RHS Hampton Court I've been pondering VP Gardens a lot lately. Last year's drought conditions set me off initially, then our harsher than usual winter combined with this summer's flip and flop weather means the thinking continues. It's a huge topic which I freely admit I'm struggling to get my head around. Tom Massey's Resilient Garden  at Hampton Court recently  tackled this topic brilliantly and was a timely interlude which gave me much food for thought. There he encapsulated the detailed research he'd found which informed both his show garden and book of the same name. I think it's one of the most important show gardens I've ever seen. It's clear the way I garden needs to change so that I have my own resilient garden. I haven't worked out the exact details yet, but Tom's book plus a couple of others (see below), alongside the rainwater management handout from the show garden's  sponso...
Read more

Chelsea Fringe 2014: Shows of Hands - Episode I

Image
The gloves NAH used to build the raised bed . The effects are L to R, top to bottom:  Original photo, Warhol, HDR, Green tint, B&W, Posterize, Boost, Cross process and Sepia Welcome to Shows of Hands - my Chelsea Fringe project for 2014! As you can see I've been having a bit of a play around in Pic Monkey for my first contribution. You're welcome to join in between now and 8th June 2014. The idea behind this year's project is to highlight the tool most precious to a gardener: their hands. How do I take part? It's simple. All you need to do is take a photo of hand(s) in a gardening context and then share it via your blog or other social media (such as Twitter or Facebook), then make sure I know you've done so. I've set up Mr Linky below for your blog contributions. The Chelsea Fringe photo on the right sidebar links to this post, so you can easily find it again when you're ready to add your contribution. If you share your photo on Twitter, ...
Read more

Testing Times: Tomatoes

Image
  I've run a couple of tomato trials this year. The first is a revisit of the biochar trial with Oxford University I attempted some years ago (with a different organisation this time), and the second is a trial of a water gadget called Plantsurge which I was given to try at Malvern Spring Show earlier this year. Most of you have probably heard of biochar already and the claim that this inert, carbon-rich material can help soil fertility and plant health. The RHS information in the above link says results can be mixed, with reduced effects found in alkaline soils. This may help to explain the lack of difference I found in my previous trial as VP Gardens is on a lime-rich soil. Plantsurge is a different beast altogether. It's a strong magnet which is attached to a hosepipe as shown in the photo above. It's claimed that it softens water, with the result more like watering with rainwater. The higher nitrogen found in rainwater is thought to be beneficial to plants. Gardener...
Read more