There’s nothing more disheartening to gardeners than seeing your prize greenhouse, invaluable polytunnel or wonderful pergola destroyed by wind, rain or snow. Box blight, Sudden Oak Death or potato blight is heartbreaking. But, given time and a wee bit help, you and nature can puts things right.

That’s a lesson the retiring Senior Horticulturist at the Royal Botanic Garden Edinburgh’s Benmore Garden has learned. Ian Potts has recently retired after 49 years. Over the years, Potts played an important part in making the garden so successful. As his daughter, Nicola, says: ‘My father, obviously very passionate about the garden, is very keen to be involved in just about every aspect, including education .. no member of staff has seen, or been involved in as many changes as my father has. The knowledge he has accumulated will be very hard to match.’

We gardeners should take heart from this accumulated experience and wisdom. Potts saw the garden escape closure after a horrendous hurricane in 1968. Greenhouses were destroyed and around 500 large trees felled, but, after three or four years, the garden bounced back from near extinction.

And Nature continued its assault on the best laid plans for the garden. At Benmore, a flood in 1998 swept away a key access bridge and devastated the Redwood tree avenue. Only three years ago, the garden was once again severely damaged by fiercesome winds. But Potts knows the garden will fully recover.

Everything is on a much smaller scale in our gardens, but plants are resilient and buildings and structures can be replaced. If this happens to you, keep things in perspective.

This also applies to pests, diseases and invasive aliens. Many of them have been introduced through global trade. In 2012, a consignment of young trees from the Netherlands introduced ash dieback to the UK. Although the disease doesn’t seem to be as bad as was first thought, two outbreaks in an ancient oak woodland at Glen Nant, near Oban and in nearby Morvern have been identified, so the problem persists. Why on earth ash trees were imported in the first place is beyond me, but this shows that we should buy locally-grown stock, if at all possible.

Likewise, another deadly tree disease, Sudden Oak Death, Phytophthora ramorum, was imported. It was probably first introduced in the 1990s in consignments of ornamental trees. Benmore was not immune and many important plantings had to be ripped up and destroyed.

During his long service at Benmore, Potts witnessed the ravages of disease on a large scale and could see that careful control and management seemed to work, so we gardeners should adopt the same approach.

Constant vigilance is essential. A new fungal disease that attacks and destroys aquilegias was identified two years ago. Aquilegia downy mildew has affected gardens in the south of England, from Devon to Essex, and a National Aquilegia Collection in Swansea has been nearly destroyed.

The owner, Carrie Thomas, reckons that she’s only got 10-20% of her plants left one year after the first sighting. There are yellowish-green streaks on the leaves, followed by fluffy white growth on the undersides, with reddish brown stem lesions a possibility. Plants always die. Sooner or later, the disease will reach us but, in the meantime, be sure not to bring or buy aquilegias from the south of England.

Sadly, with an ever-increasing plethora of new diseases, there isn’t enough funding available to eradicate them or breed alternatives. But where there’s a financial will there’s a way. The popular bedding plant, busy lizzy has been devastated by another strain of downy mildew. But because a frighteningly large number of gardeners actually like this plant, researchers have been engaged to develop a New Guinea hybrid with good disease resistance.

Play your part

With all these new pests and diseases, it’s important to keep track of developments and volunteers are needed for this. Many different organisations, including the Woodland Trust, want to recruit volunteer ‘citizen scientists’. Volunteers help carry out early surveys for tree pests and diseases. They ensure Tree Alert reports are complete and of high quality, enabling scientists at Forest Research and Fera [Food and Environment Research Agency] to carry out a correct diagnosis. They provide further accurate data allowing scientists to identify trends in the spread and appearance of pests and diseases

All volunteers are trained annually by Forest Research and Fera scientists. Training enables them to correctly identify signs and symptoms of Observatree’s 20 priority pests and diseases as well as carry out site surveys. Volunteers are also trained to collect bark, soil and foliar samples, following biosecurity procedures. [http://www.observatree.org.uk/]

Plant of the week

Cyclamen hederifolium, Ivy-leaved Cyclamen, has delicate, lightly scented flowers with reflexed petals. The heart shaped foliage that follows is marbled and patterned in shades of silver and green, often with a purple underside. Height, 10cm, spread: 15cm. (6").