Category Archives: Annuals

Large-flowered Collomia: Collomia grandiflora

Some annuals have such an elegance and simplicity about them that they will fit in with iny form of planting. .arge-flowered Collomia is such a plant.

This Collomia is tall and will reach up to 75cm (30in) in good conditions. It has an old-fashioned :harm and presence; the lowers being held in jomes on the ends of branching stems. Usually, one or two bands of lowers are open at any one time around the green dome. Their unusual creamy colour blends well with a wide ange of other flowers, rom bright red to yellow and blue, and can be very useful as a link between two difficult colours, especially if they are planted in a drift.


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The flowers appear in mid Summer, but before this, the plant itself makes an attractive addition to the border The leaves are a good fresh green, which is set off by a red flush to the branching stems. When the flowers have faded, however, the plants soon become jaded and tired-looking; it is then time to remove them.

It is unusual to grow these plants in pans and then plant them out; they are normally sown where they are to flower. Whichever method is used, plant or thin them out to a spacing of about 25cm (10 in). While it is not essential to thin, if you don’t, the plants will be smaller.

Collomia prefer a sunny position, but they seem to grow well in the shade of a North-facing wall.

They are not too happy in dry Summers, which shorten their flowering period. Watering will help in such conditions.

These plants will grow in any good garden soil. They grow best if it is reasonably rich and moisture-retentive.

Being hardy annuals, any emerging seedlings will manage to cope with what remains of the Winter without any problems.

The only way to grow Collomia is from seed. This should be sown in March where the plants are to flower. They produce quite a lot of seed and self-sow quite readily. After the first year, it is rare to have to sow them again. Whether sown or self- sown, they will need thinning as mentioned.

Several other interesting annual Collomia are in cultivation: C. biflora has attractive clusters of bright scarlet flowers and sometimes is listed as C. coccinea; C. linearis is shorter with pink flowers. All the Collomia are still sometimes listed as Gillia.

Campanula Canterbury bell

Height: 45-90cm (17-3ft) Planting: distance 30cm (1ft) Features: flowers spring to summer Soil: ordinary, well-drained Site: sun or partial shade Type: biennial The Canterbury bell (Campanula medium) is a typical cottage garden plant – easily grown, and showy in flower. It is best planted in small groups throughout a border, which it seems to fillContinue Reading

Celosia cockscomb, Prince of Wales’ feathers

Height: 23-38cm (9-15in) Planting: distance 23-30cm (9-12in) Features: flowers summer to autumn Soil: rich, well-drained Site: sheltered sun Type: half-hardy annual Celosia cristata ‘Dwarf Fairy Fountains’ ‘Dwarf Geisha Mixed’ has attractive, small plumes in a wide colour range. ‘Jewel Box Mixed’ has crested blooms in mixed colours: red, pink, salmon, gold and yellow. The plantsContinue Reading

Callistephus China aster

Height: 15-75cm (6-30in) Planting: distance: 20-45cm (8-18in) Features: flowers summer until first frost Soil: ordinary, loamy Site: open, sunny Type: half-hardy annual Just one species, Callistephus chinensis, is responsible for the many varieties of China aster on the market – tall and dwarf, single- and double-flowered, mixed and single colours. The flowers looklike a crossContinue Reading

Calendula officinalis Pot Marigold

Height: 30-60cm (1-2ft) Planting: distance 30-38cm (12-15in) Features: flowers spring until first frost Soil: well-drained, ordinary or poor Site: sun Type: annual This is one of the easiest hardy annuals to grow and, with its glowing daisy-like flowers of orange, cream or yellow, one of the brightest. It flowers from late spring until the firstContinue Reading

Calceolaria slipper flower

Height: 20-30cm (8-12in) Planting distance 25-30cm (10-12in) Features: flowers summer to autumn Soil: light, rich Site: sheltered sun or partial shade Type: half-hardy annual The curious, kidney-shaped blooms of the slipper flower were favourites for formal bedding schemes in Victorian gardens. Calceolaria integrifolia and its subsequent varieties can be grown outdoors, but they must beContinue Reading


Originating from Australia, this attractive annual bears star-like flowers from early summer to autumn in cooling shades of blue, purple and white. The plants are ideal for a window box or container growing and will perform equally well grown in a sunny border. Popular varieties: The following varieties are easily raised from seed. ‘Blue Star’Continue Reading

Bellis double daisy Swan River daisy

Height: 15-30cm (6-12in) Planting: distance 20-25cm (8-10in) Type: half-hardy annual Features: flowers spring to summer Soil: ordinary Site: sun or partial shade From the familiar wild daisy come several bigger, brighter, garden varieties which are ideal for edging flowerbeds or mixing with other plants in window boxes and containers. They have white, pink or red,Continue Reading

Begonia begonia

Height: 15-30cm (6-12in) Planting distance: 20-25cm (8-10in) Features: flowers summer to autumn Soil: rich: moist, well-drained Site: sun or partial shade There are now two recognised types of begonia for summer bedding and container growing: Fibrous-rooted begonia (begonia semperflorens) and its varieties are grown as annuals. The plants, which generally reach 15-30cm (6-12in) high, areContinue Reading

Annual woodruff Asperula orientalis

Height: 30cm (1ft) Planting distance: 7.5-10cm (3-4in) Features: flowers summer Soil: ordinary, moist Site: partial shade Type: annual Annual woodruff (Asperula orientalis, syn. A. azurea, A. setosa) is the only hardy annual in this genus of 200 species – all other woodruffs are treated as perennials . Its pale blue flowers are strongly scented –Continue Reading