Hardy Geraniums

Speaker: Thomas Stone, MCI Hort, MPGCA
Date: 26th April
Year: 2017

Thomas told us there were 900 species/varieties on the market; they are the most noticeable of all the garden varieties, go well with roses and should not be confused with Pelargoniums. They will survive in a great range of conditions from dry and sunny to deep shade. The “cranesbill” common name is due to the long-pointed seed capsule. He then went on to describe a number of the different categories and the conditions which they prefer:

 

Asphodel ides
White or mauve flowers, like dry, sunny, Mediterranean conditions, will flower till the first frosts. A nice variety is “Prince Regent”.

Cantabrigiense
Originally from Eastern Europe, a dwarf variety with pink flowers, “Cambridge” likes sun or shade, makes a good edging plant.

Macrorrhizum
Pure white, taller “White-Ness” has apple scented leaves.  “Bevans” deep pink or purple likes dry shade and is shallow rooted, make good ground cover.  Other good varieties include “Kashmir White” spreading, “Mavis Simpson” light pink and “Jean Armour”

Riversleaianum
Hybrid “Russell Prichard”, 2’ tall and wide, vibrant pink, is tolerant of most conditions except waterlogged soil but is less tolerant of shade than many cranesbills, and thrives in full sun.

“Dreamland” white.

“Wlassovianum” likes moisture, easy and the leaves are flushed with purple-bronze in spring and summer and red in autumn. Bears loose sprays of long-lasting, purple-pink or pink flowers with five distinct petals, from midsummer to early autumn.

Himalayense
“Gravetye” up to 12” tall, perfect blue spectacular flowers and spreading.

Not to be mixed up with “Johnson’s Blue”

“Brookside” 1970 but not for retail until 1989, purple with lovely lacy leaves.

“Malviflorum” a native of southern Spain. Flowers disappear after flowering, but the large rich blue flowers, red-veined, are very lovely in May. 12” tall.

Oxonianum
Very good ground cover.

“Thurstonianum”, makes a magenta pink carpet and will take deep shade and full sun. Light green, 5-lobed leaves and with very narrow petals.

“A T Johnson”, light delicate pink.

“Claridge Druce”, Rose pink.

“Wageninum”, salmon pink.

“Waters Gift”, exceptional; white with purple veins.

Phaeum
“Samobar”, deep purple pink, also called Mourning Widow and dusky cranesbill, leaves splashed with purple.

“Joan Baker”, will take deep shade.

“Alex’s Pink”, loved by bees.

“Rose Madder”, deep intense pink.

“Connie Broe”, yellowy, mottled leaves, deep purple flowers.

“Margaret Wilson”, pale yellow, cut out leaves, variegated, lilac purple flowers.

Pyrenaicum
“Bill Wallis”, grows well from seed, best as an annual, self seeds, small purple/blue flowers, can be grown in the dry garden.

“Isparta”, clump forming light mauve flowers, self seeds.

Renardii
Soft small rounded leaves, 6/9” clumps, need to be kept short of nutrients to get good flowering. Almost white flowers.

Sanguineum
Bloody Cransbill, a deep red British native.  Also “Album”, white will make good alpines.

“Striatum”, very dwarf; white; delicate.

“Elke” from Belgium, candy pink flowers and bronzy autumn foliage, does not come true from seed.

Sylvaticeum
“Birch Lilac”; violet-blue flowers on this Canadian cultivar. For shady or open positions and drought tolerant but will give better results with humus and moisture.

“Blue Sunrise” which has yellow foliage, sky blue flowers, and clumps up.

Magnificum
“Wisley Blue”; clumps up.

“Ann Folkard”; will scramble up into shrubs, stunning pink flowers and leaves edged with red.

Pratense
lovely, native meadow cranesbill.

“Mrs Kendal Clarke” a compact clump forming plant with jaggedly-lobed leaves and light grey-violet flowers.

“Summer Skies”; double pale lilac flowers.

“Black Beauty”; requires dampish soil. Striking dark foliage, ideal for ground cover where the beautiful pinkish-red flowers can catch the eye.

“Rozanne”; vigorous, outgrows its spot, just trim it back.  Masses of saucer shaped, violet-blue blooms with dainty white centres. Flowers repeatedly throughout the summer and won’t self-seed like other Geraniums.

Maculatum
“Espresso” Leaves are bronze-coloured, contrasting with pale purplish-pink flowers borne over a relatively long season from late spring to summer likes semi-shade.

Sessiliflorum
“Nigricans” from New Zealand, very dwarf alpine with delicate white flowers and red leaves.

Finally, two very similar varieties from Madeira, which require slightly different growing conditions and are often mistaken for each other, both have bright pink (fuscia) flowers:

(i)  Maderense
Also, a white version called “Guernsey White”

(ii)  Palmatum
Slightly tender, 2’ in height can be found in The Porter’s Garden in Portsmouth Dockyard.

After a thoroughly enjoyable if technical talk, Thomas’ final advice was to reduce the spread of plants by cutting around the outside of the plant with a spade when needed, and to take basal cuttings or divide the plant in autumn.

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