A damp but relatively mild day heralded the start of less bitterly cold, albeit dull and rather miserable weather in this very late spring. Nevertheless, the hall looked full of colour and the benches were mostly well filled, except perhaps for the large pan sizes, where some gaps were discernible.

This did not dissuade Frank and Barbara Hoyle from bringing six immaculate heavyweights to grace Class 1. This repeated (and arguably even excelled) their achievement the previous week, two of their AGS Medal plants being awarded Certificates of Merit on this occasion. Dionysia aretioides had also been certificated at Cleveland, where a stablemate won Best in Show. Here it was joined by an exemplary Primula allionii ‘Mrs Dyas’. The Hoyles also won the large three-pan class for rock plants from different genera, a further illustration of the depth of their collection of large plants of high quality.

Elsewhere in the show, also for the second week running, the Hoyles won Best in Show, the Farrer Medal being awarded to a superb Pulsatilla vernalis showing more than 40 erect chalices, with more in bud. This was of Picos de Europa provenance (the species occurs more widely throughout mountainous parts of Spain than is generally realised), plants of this origin seeding freely around the exhibitor’s garden.

Almost as soon as I entered the hall, my eye was taken by Clare Oates’ beautiful pan of Fritillaria carica, carrying nearly 30 stems, many bearing two bells of a slightly greenish-yellow. This winner of the Chatsworth Trophy for best bulb had resulted from a sowing in 1994. One suspects that careful selection and propagation over some quarter of a century had resulted in the immaculate uniformity of the exhibit.

Clare joined several other exhibitors in benching a fine pan of Tulipa iliensis. I confess that this medium-sized golden tulip was new to me, although it is now fairly widely available. It hails from gravelly sub desert scrub at moderate altitudes (400-1,400 m) in Xinjiang and Kazakhstan, so would presumably appreciate a good summer baking. It has a delightful scent and has been christened the ‘Cowslip-scented Tulip’ on the RHS website. Some forms show redder backs to the tepals than those on exhibit.

The outstanding genus at this show was undoubtedly Corydalis, and there was a great variety of species and hybrids to enjoy. Amongst the latter was Don Peace’s C. maracandica x popovii. Don’s C. maracandica had set seed in 2009 and this was sown immediately in late April. The mature seedling shown bore a much closer resemblance to the C. popovii growing nearby than it did to its mother, so this chance miscegenation was readily detected and had resulted in a densely-flowered plant with rather shorter spikes than is typical of its father.

Tommy Anderson’s Corydalis glaucescens was also much admired. The essentially white flowers bear a long straight spur, emarginate lower petal and bluish leaves, the combination of features being diagnostic in this complex genus. It was also interesting to see so many named varieties of Corydalis solida. In many gardens this species increases well by means of both vegetative splitting and seed. Clearly, it is possible to maintain the distinctiveness of really worthwhile named varieties by the former method, but it is very easy to lose track of these amongst a welter of (mostly excellent) self-sown seedlings, so the acquisition of named seedlings is best treated with caution. Here we saw ‘Merlin’ (white with a lilac frill), ‘Frodo’ (pale lilac), ‘Falls of Nimrodel’ (pink and reddish), ‘Penza Strain’ (red) and ‘Lentune Rouge’. Incidentally, Google tells me that this refers to the jersey worn by the last rider in the Tour de France!

Your reporter was lucky enough to visit a few of the best Czech rock gardens a few years ago. One of my abiding memories was a waterfall of the blue Callianthemum farreri spilling down a scree slope, a species which seemed quite widespread amongst their aficionados. This is still a rare plant in the UK, so that the 12 denim-blue blooms exhibited by Alan Furness will have been the first sighting for some. This plant was in fact a seedling grown from the crossing of two imports which originated from Mojmir Pavelka.

Hyacinthoides italica is a good example of a worthwhile plant that often slips under the radar. It is quite widespread in southern, subalpine slopes of the Alps, usually on limestone, growing in partial shade. Given a warm, well-drained site away from strong sunlight, it is a good garden plant, and also performs well in a pot as long as the bulbs never dry out. It has a delicacy missing elsewhere amongst the bluebells. Shown here by Les Brown, a pan packed with flowering stems in ace condition was overlooked by judges who clearly preferred more fashionable fair.