A group of garden-raised hybrids between H. elliptica and H. speciosa. They are shrubs of dense habit, usually under 4 ft in height. Stems rather stout, glossy, with two bands of down on each internode. Leaves rather formally arranged in four rows at right-angles, obovate to almost elliptic, obtuse and usually apiculate at the apex, distinctly stalked, palish green, slightly fleshy in texture. Flowers very large (up to 1⁄2 in. wide across the lobes), violet-blue, pinkish purple or sometimes white, arranged in simple axillary racemes 2 to 3 in. long; tube broad, about as long as the calyx.
Although long known in gardens, this hybrid was first validly described by Miss Alice Eastwood in 1943, from a plant cultivated in the Golden Gate Park, San Francisco, under the name “V. decussata”. The first recorded cross between H. elliptica and H. speciosa was made before 1859, in which year a gardener signing himself ‘Devonian’ sent a specimen to the editor of the Gardeners’ Chronicle from a hybrid between these species which he had made. The original plant was then 4 ft high and 22 ft in circumference and bore violet-blue flowers (Gard. Chron. (1859), p. 563). In the same year and in 1860 the Royal Horticultural Society distributed some seventy plants to its members under the name “V. decussata devoniana” and it seems almost beyond doubt that these were the hybrid raised by ‘Devonian’. The same cross was also made by Isaac Anderson-Henry of Edinburgh before 1862 and named by him V. lobelioides. The variety ‘Blue Gem’ was raised in 1868 by H. W. Warren, a nurseryman of Salisbury, who found it growing as a self-sown seedling in the root-ball of a potted azalea. When noticed it bore only its first pair of leaves, yet so rapidly was the plant multiplied that by the autumn of the following year ‘Blue Gem’ had received five First Class Certificates. Warren sold the stock to Messrs Cripps of Tunbridge Wells, who put it into commerce (Journ. of Hort. (Nov. 30, 1876), p. 472).
H. × franciscana is common in coastal gardens of the Atlantic zone, but is not reliably hardy inland. Young vigorously growing plants are very vulnerable to frost but may become hardier if they can be brought through the first winter. It is one of the most wind- and spray-resistant of shrubs and much used for hedging in the Isles of Scilly, where it is known as the ‘hedge veronica’.
In H. × franciscana ‘Variegata’ the leaves are margined with creamy white.