MEADOW rue in its varied forms is an indispensable border flower. Light and airy, it brings a dignified presence to the garden from May to August. Good fertile soil in sun or part shade is its requirement and once settled in it increases most pleasingly by seeding itself.
Profligate tendencies can sometimes become a nuisance in the garden even an embarrassment but I have never regretted the extravagance of the meadow rue family.
In general, foliage and flowers are attractive and the graceful stems and sprays expand from a discreet and compact crown and root system. This means lots and lots of individual plants can be accommodated in a restricted space without any suggestion of thugishness or the bad manners of an unruly mob. Instead, there is an air of grace and charm, an elegant presence which enhances other flowers and foliage.
They could never be considered to add structural form or an architectural presence to the garden in the way that a hosta or a cardoon might their use is quite the opposite they add the froth and lightness which is the seasonal dressing of summer.
The most useful for early summer is Thalictrum aquilegifolium, appropriately named as the leaves and stems fairly closely resemble Aquilegia or Granny's Bonnets. There the resemblance ends as the blossom on this Thalictrum is a broad head of fluffy, flouncy flowers. It is excellent value in May and June, even lasting this year in somewhat shaded spots into July. The stems can grow to three feet or more in height and rarely need staking. The colour varies from creamy white to lilac pink and purple. When different colours are grown in a garden they will mingle and cross, producing interestingly shaded offspring.
As that one finishes flowering Thalictrum speciosissimum or the somewhat similar looking Thalictrum lucidum begin to take over. In some forms, the Thalictrum's foliage is a glaucous blue green, in others lime green while T.lucidum has shiny green laciniate leaves.
Like T.aquilegifolium, these are natives of Europe and parts of Asia. The flowers are again fluffy heads, this time in pale lemon yellow. In the form with glaucous blue green foliage the colouring is especially delightful.
The flower stems can reach up to five feet or even six feet height but as the overall effect is one of lightness and elegance, the plant is not overpowering and can be happily sited in small gardens. It will flower for about four weeks and can be quickly tidied up afterwards. The dead heads having been removed, the foliage will continue to add interest through late summer into autumn.
At flower time, they go beautifully with blue campanulas, monk's hoods or delphiniums. Depending on the particular situation they may need staking but that minor effort is well worthwhile.
Rabbits and slugs seem to take no interest in the meadow rue family so they are relatively trouble free.
In July and August, the finest of all the family makes a distinguished addition to the garden. What is that mauve gypsophile?" is a frequent question from those not familiar with the plant. It is actually much nicer in every way than gypsophila. Sometimes labelled T.dipterocarpum, this one comes from China where it grows in alpine meadows and scrub.
The foliage is fine and dainty and tall stems up to six feet high, hold broad, loose, conical heads of tiny lilac mauve flowers which have creamy yellow stamens. A most telling plant, it could be placed quite comfortably even at the front of a border. There is no sense of bulk or mass, only lightness and transparency.
WHEN happy in a rich soil it will increase by seeding about. You could never have enough of it. The better the soil the taller it will grow.
There is a white flowered form available and I only wish that it would develop really profligate ways. Occasionally a seedling appears which is halfway between the mauve lilac form and the white. These are usually a washed out pale lavender blue.
Fortunately, the double form of Thalictrum delavayi Hewitt's Double is becoming more widely available. This does not seed but can be increased by division or by cuttings. The individual mauve flowers are folly double tiny rosettes without the creamy yellow stamens. It is a delight, one to be treasured and cared for.