June in the Garden

If the garden in May was fresh and thrusting, in June there is a bit more stature about it, foliage has toughened up and had its youthful glow dulled by exposure to the vagaries of the UK climate. As with so much about gardening in this country, what the weather has done, and is doing, has a large bearing on what the garden is looking like. Last year it was very dry, in early spring, which meant that some plants were already suffering by this point. As I write this, we’ve not had any exceptionally hot or dry spells, I may have spoken too soon, and the garden is very much ‘steady as she goes’.
Wind is one aspect of the weather, unlike the more subtle rain or shine, that can destroy a garden in a matter of minutes. Strong winds and summer storms have the ability to beat down and blow over plants which are now in full leaf and at their most susceptible. There is a good reason why most plants lose their leaves during the winter months; a shrub or tree in full leaf is at much greater risk of losing limbs, or being blown over—it’s just physics.
You may not be able to stake a mature tree, or large shrub, but it is worth checking that any plants that need support, be it with pea-sticks or canes and string, are catered for. Climbers and wall trained specimens should be checked over and any ties that have failed, or were missed, last time they were pruned / tied-in, need to be replaced before the climber in question can peel itself off the structure its attached to.
I remember having to do an emergency intervention on a Fremontodendron californicum that was trying to detach itself from a trellis, on the front of a large house in Hartley Wintney. The task was completely torturous thanks to the nasty, irritating, little hairs that it is covered in and which are shed on contact. Having said that, Fremontodendrons are one of those useful wall trained climbers that are seldom seen these days and are definitely worth considering, despite their irritant potential.
Back at ground level; some tall-growing border perennials are notoriously brittle, delphiniums are a case in point, and trying to rein them in whilst in full sail is a thankless task. Your best bet is to keep some pea-sticks in reserve and these can be shoved in, against the clumps of foliage, for emergency shoring up. Canes and string will do the job but it’s really fiddly trying to get in amongst the stems in a way in which won’t show.
I have a particular aversion to those wire stakes, covered in green plastic, which are meant to link together around wayward perennials. They never seem to provide the support where it’s needed and always stop ‘holding hands’ just at the point when the plant is threatening to collapse. They also have a nasty habit of getting in the way of your secateurs, with blade blunting consequences, during the autumn cut back… or getting left on the lawn where, thanks to their green disguise, they can lurk, unseen, waiting to cause havoc to your lawnmower!
As mentioned last month; cutting out the flowered stems on mature shrubs, which have finished flowering, is a task that needs to continue as the summer progresses. Cutting out the oldest stems helps to keep the shrub vigorous, rejuvenated, so that it continues to earn its keep in the garden as the years go by. It’s much better to keep removing the oldest stems, as they exhaust themselves, than to let the shrub just get bigger and bigger, more and more congested, until your only option is complete removal or an unsightly ‘cut to the ground’ rejuvenation.
Shrubs are not the only garden plants that benefit from having their spent flowers removed. Unless the plant is grown for it’s ornamental fruits or seed-pods, such as hips on some specific roses, like Rosa moyesii ‘Geranium’, then pruning off the flowers once they’ve faded is good practise. Many early flowering herbaceous perennials will have a second flush of flowers if the plant is cut back after first flowering. Incorporating a gentle feed, something like ‘fish, blood and bone’ tickled in around the plant, will help the plant to bounce back for a repeat show in a few weeks time.
Now that tender perennials and bedding plants have been outside for a while they are prime candidates for dead-heading and, in fact, will require diligent old flower removal for the whole of the summer if they are not to ‘run out of steam’. Similarly, they will benefit from liquid feeding at every other watering, following the label instructions on your favoured plant food, as continually producing blooms over a long period is a big ask for any plant.
Garden pests can get out of hand this month because they have plenty of lush new foliage to devour and the warmer summer temperatures maximise their breeding potential. Regular checking and removal, by whatever method you favour, is the order of the day. Before using chemicals remember that these can upset the delicate balance between the plant pests and their natural predators so using them may actually result in worse infestations a few weeks down the line. If you can bear to remove the pest by hand, or with a jet of water, it may prove enough to keep their numbers down while the natural control predators get a chance to build up their numbers.
I doubt that I really need to remind you that the lawn will need regular cutting, now that it is actively growing, and the cutting height of your mower can be reduced to the shortest setting that your topography allows without scalping the sward. As ever, I’ll point out that lawns should never be irrigated, no matter how hot and dry our summer is. Personally, I’m in favour of ‘not so hot’ English summers, but if we do have a drought then raising the cutting height, temporarily, will at least reduce some of the stress on the grass while still preventing lawn weeds from setting seed and taking over.
If you have a pond, June is a good month to perform maintenance tasks such as thinning out water weed or marginal plants. It’s warm enough that the job is not too unpleasant for you, always an important consideration, plus any new plants that you add will get off to a good start. I’ve got to admit that my own pond has now been completely covered by duckweed, after many years of being free of this particularly pernicious floating pond plant.
A blanket of duckweed totally excludes light from the pond which is detrimental to other pond plants and pond life in general. I think its caused by a shift in water quality, probably a sign that there is too much organic matter rotting down on the pond floor because, previously, although present, it never got out of control. Continually scooping it out with a net is my only option, until I can get around to tackling the underlying problem.
I don’t like to end on a negative so, to get away from the duckweed, June is a great month to log onto the ‘National Gardens Scheme’ website and seek out the many local gardens that open for charity as they reach peak horticultural perfection.