What is 'The June Gap'

There is a time in early summer when the best of the spring flowers and fruit blossom is over, but the height-of-summer flowers are not yet in full bloom.  Beekeepers are familiar with the concept of the ‘June Gap’ - a crucial time for beekeeping when nectar and pollen may be in short supply and if you want to keep the honey flowing, you need to have plants around your garden that supply your bees with what they need.  This applies to all native insects that depend on nectar and pollen as a food source, so if you are a keen wildlife gardener and like to cater to the needs of your invertebrate visitors, then it is worth ensuring that there is no gap in the nectar flow at this time.  An added bonus of course, is that the garden will look bright and colourful now if you choose your plants with care, and there are some wonderful shrubs, herbaceous plants and wildflowers coming into bloom in June.

So what insects are around now that we would perhaps like to give a helping hand and thus see more frequently?  June is actually a good month for garden butterflies including the large, small and green veined whites, early migrant painted ladies and red admirals, brimstones, small tortoiseshells and some of the ‘browns’ such as speckled wood and meadow brown.  If nectar is in short supply in your garden, these lovely insects will look elsewhere.  Then of course bumblebees will be in the throes of building up their colonies in late spring and early summer.  The queen will have established her nest and the first generation of workers will be collecting pollen for the new brood of bee larvae, so this is a crucial time for these lovely insects.  And while they are foraging for food they will be pollinating for you, so it is a mutually beneficial arrangement if you can ensure they stay around in your garden.

Other bee species too will be seeking pollen and nectar.  The red mason bee will be reaching the end of its breeding season, but the blue mason bee is most active in June and July and is also a resident in our gardens.  Other solitary bee species including the leafcutter bees are also very active now.  So even though most of us are not beekeepers, there are still more than enough reasons to keep the nectar flowing and the pollen supplies topped up, and there are plenty of excellent plants waiting to burst into flower.  

Perhaps the best place to start is the herb border or any sunny space where herbs will thrive.  They must of course be allowed to flower to be a source of nectar and pollen, and far too many of us cut our herbs (understandably) for the kitchen, to prevent flowering and ensure a continued supply of succulent leaves.  Perhaps the answer is to have at least a few plants that are allowed to do their own thing – your garden insect wildlife will benefit from this approach.  Rosemary is perhaps the exception, where old woody stems are likely to flower whatever you do to them – and the flowers are amongst the very best for both nectar and pollen for all types of bee.  Rosemary is not the hardiest of plants though, so make sure that a few cuttings are taken in August each year to cover any winter losses – it’s a plant no garden should be without.  Another herb that can be allowed to flower to every bee's delight is borage, whose bright blue blossoms are a bee magnet.  If this annual is allowed to self-seed, it will flower from this month onwards.  Other excellent herbs in June are thyme, chives, catmint and lemon balm, all of which are appealing to bees and also some butterflies.   Small tortoiseshells love thyme, while the whites and brimstones are attracted to catmint and lemon balm.  The latter has the added bonus of providing a seed source for goldfinches later in the year.

In the fruit and vegetable garden, which after all is where you really want the bees, all the soft fruit will provide nectar and pollen through late spring and into early summer. Raspberries in particular should still be flowering in June and if picked as they ripen will continue for a while through the summer.  Some later gooseberry varieties will also flower now and broad beans sown in succession will have bees in attendance.

Where wildflowers are concerned there are of course plants flowering throughout the year.  Even the depths of December may see the occasional bright pink herb Robert flower with its delicate darker veins – a delight in the middle of winter.  But June is a good month for flowering native species and several are excellent garden plants for corners, meadows or even in amongst border plants.  The oxeye daisy begins its flowering period in May, but continues into June and even July the further north you are.  Few wildflowers can rival the spectacle of swathes of this glowing white flower on roadside verges and in ancient meadows, although in the garden it can take over a little!  Plant it into meadow grass to fully appreciate it and provide both nectar and pollen for a wide range of insects including the beautiful marbled white butterfly, which appears this month in some areas.  Other wildflower beauties include cornflower, viper’s bugloss, rock rose, purple loosestrife, musk mallow, field poppy, and stonecrop.  If you are happy with a slightly ‘wilder’ garden, thistles of all sorts will start to produce their nectar this month and continue for some time to attract a wide range of butterfly species as well as bees.

In the border or in containers perhaps, the most exuberant selection of pollen producers this month are the hardy geraniums. These superb plants come in many colours and shapes, and just about every variety is worth growing, especially Geranium phaeum which smaller bumblebees adore.  Some campanulas including the beautiful C. latifolia will begin to flower this month, and if you like them, Canterbury bells are also great for bumblebees.  You could also try the mountain cornflower (Centaurea montana), oriental poppies and the annual Californian poppy, which is an excellent pollen provider.  Some trees and shrubs are good this month including Buddleia alternifolia which comes into bloom a month earlier than its more familiar cousins.  Ceonothus thysiflorus, the Californian lilac is a joy, its sky blue flowers buzzing with honeybees, and Choisya ternata, the Mexican orange blossom, will have pollen.  Pyracantha, Cotoneaster, Cytisus (broom), Philadelphus and open types of roses are all excellent and if your soil is light, pollen bearing Cistus, the sun rose with its delicate petals, could be a highlight in a sunny spot. Some of the Berberis varieties flower into June and don’t overlook our native shrubs.  It is easy to completely miss the smaller flowers of dogwood, spindle and holly (only hawthorn really shows off in May and June) but they are invaluable at this time.  A mixed native hedge is a lifesaver for insects in early summer.

Perhaps, having looked at the available flowering plants for early summer, we don’t need to be too concerned about our garden insects after all!  Beekeeping is a demanding occupation and even if you have only one hive of 50,000 bees in your garden, the responsibility of ensuring they are well fed is great.  But a thoughtful gardener can easily keep wild solitary bees, bumblebees and butterflies happy with a colourful selection of pollen and nectar producing varieties over the next few weeks, to guarantee that the requirements of these beneficial insects are well met.


© Text and photographs Jenny Steel 2017