Plants for your Balcony and Window-Boxes
1 Gaillardia (Grandiflora-Hybrids): Blanket Flower
2 Coreopsis X grandiflora: Tickweed
3 Helenium x autumnale: Sneezeweed
4 Rudbeckia nitida: Coneflower
Theseare allied not only in that they all belong to the same family but also in that they all (or at least the parent species) are native to Florida, where they grow as perennials. In Europe, however, they are often killed by frost (except for helenium) and so it is advisable to sow them anew every year.
Gaillardia hybrids are derived from the type species Gaillardia aristaia, G. pulchella, and perhaps several more. The choice of cultivars is large, ranging from small forms about 20 cm (8 in) high (’Kobold’ — red yellow) to ones reaching 80 cm (32 in) in height (’Sonne’ — golden yellow tinted orange). The seeds should be sown in boxes in March and the seedlings put out in their permanent site in May. It is recommended to provide them with a good protective cover of evergreen twigs for the winter.
Coreopsis is even more tender; usually it lasts only two or three seasons. It grows to a height of about 50 cm (20 in) and some forms have flowers up to 9 cm (3-1/2 in) across (’Badengold’). It has the same site requirements as the preceding species, but whereas gaillardia is grown in rich humusy, coreopsis does better in rather poor, light, sandy soil.
Helenium is a well-known and very popular plant that is found in practically every garden. Like the other flowers it can be grown not only in an open bed but also in a large earthenware urn. Helenium likes deeper, rich, moist soil in full sun. It flowers from late June until the frost.
The last plant, rudbeckia, grows in similar places but ones that are slightly shaded. It reaches a height of about 120 cm (4 ft), the lovely cultivar ‘Herbst-sonne’ even as much as 2 m (6 ft). A light protective cover in winter is likewise recommended for this plant. Older specimens that have survived the winter in good condition may be readily propagated by division of the clumps.