Cosmos bipinnatus ‘Cosimo’ is a series of colours and forms of, what must be, one of our most favourite summer flowering annuals. The series has received recognition, each variety being awarded one of the most prestigious horticultural awards, the Fleuroselect Award.
This series of semi-dwarf varieties grows to a height of 50 to 60 cm (20 to 25in), with a spread of 40cm (16in), they can be used together and give a wonderful effect when planted in combination or in large drifts.
Cosmos bipinnatus 'Cosimo Red-White' blooms with beautiful bicoloured flowers, each striped in purple-red and white
Early flowering and uniform, the plants are a useful height and are short enough to be used at the front of the border, they can also be used in larger container planting. They will start to bloom in as little as 70 days from sowing, going on to offer to six months of colour from May to October - keep on top of the deadheading and new flowers will just keep coming.
Cosmos bipinnatus, commonly called the garden Cosmos or Mexican aster, is a medium-sized flowering herbaceous plant native to Mexico. The species and its varieties and cultivars are popular as an easy to grow ornamental plant in temperate climate gardens.
The plants are ideally suited for the patio and terrace, while in the border, it is a true eye catcher. These compact cosmos plants do not require staking and are the perfect option for exposed gardens where taller varieties would be blown about by the wind. Use the blooms en masse for an elegant feel to your displays, if not, set them in combination with other annuals to complement pastel shades or calm hot colours.
With all eyes on these easy to grow summer performers, Cosmos lovers will simply adore this new addition to the colour range.
Sowing: Sow indoors March to April, or sow outdoors April to May
Sow indoors in early spring 3 to 4 weeks before planting outside, alternatively, the seed can also be sown directly where they are to flower in mid to late spring. They will take approx 70 days from sowing to flowering. Keep soil moderately moist during germination. Plant out three weeks after sowing at a 25cm (10in) on a sunny or half sunny spot.
Use well drained soil and cover to a depth of 3mm (1/8in). When large enough to handle, transplant the seedlings into small pots to grow on. Acclimatise to outdoor conditions for 10 to 15 days before planting out after all risk of frost 15cm (6in) apart.
Prepare the ground well and rake to a fine tilth. If sowing more than one annual in the same bed, mark the sowing areas with a ring of sand and label. Sow 1mm (1/18th in) deep in rows 30cm (12in) apart.
Sow seed sparingly or they will choke out other seedlings.
The seedlings will appear in rows approx 6 to 8 weeks after planting and can be easily told from nearby weed seedlings. Thin the seedlings out so they are finally 25cm (10in) apart. Carefully replant thinned plants.
When the seedlings have three pairs of leaves, pinch out the tips, leaving at least one pair of leaves.
Only water in an extended drought and do not apply large doses of fertiliser as flowering will be suppressed.
Stake the taller varieties with a single or tripod of canes and some twine. Cosmos foliage is finely-cut into threadlike segments. When flowering, the taller varieties may become top heavy. This problem is alleviated when grown in groups, as the bi-pinnate leaves interlock, and the colony supports itself.
Deadhead to prolong flowering and encourage new flower buds. At the season's end, don't be too quick to pull up withering cosmos plants. Birds (particularly gold finches) love to snack on their seedheads in autumn, and the seeds that they miss may drop to the ground and reward you the next year by sprouting into a whole new crop.
Cosmos is a cut-and-come-again bloomer, meaning that the sooner you cut the blooms, the quicker new buds will pop up to replace them. The blooms appear so profusely that you'll still have plenty of colour in the garden after you've picked your flowers.
If you sear the stem end in boiling water for twenty seconds they will last a week in water.
Cottage/Informal Gardens, Flowers Borders and Beds. Container Planting.
Cosmos have been reassuring gardeners ever since the 1930s, when breeders first coaxed cosmos to bloom earlier than the native Mexican species, the flower-growing public has been hooked.
Like many of our warm weather annuals such as marigolds, Cosmos originated in Mexico and South America. Spanish priests grew cosmos in their mission gardens in Mexico. The evenly placed petals led them to christen the flower "Cosmos," derived from the Greek kosmos, the word for harmony or ordered, or balanced universe. From this we also get the common name of "The Mexican Aster".
The species name is from the Latin bipinnatus meaning “twice-pinnate” The botanical epithet is from the Latin pinnatus meaning “with leaflets arranged in opposite pairs.
Fleuroselect is the international organisation for the ornamental plants industry. Its main activities include the testing, protecting and promoting of new flower varieties. Membership includes breeders, producers and distributors of ornamental varieties. Fleuroselect is run by the members, for the members. A small secretariat operates from the organisational headquarters currently based in Noordwijk, The Netherlands.
In order to support and stimulate the development of new ornamental varieties, Fleuroselect conducts trials of new varieties entered by members on approximately 20 private trial grounds spread across Europe. Both indoor and outdoor trials can be conducted. Through the trials, the newness, the practical use, the quality and the exclusivity of the entries are determined. Genuinely new varieties receive recognition either as Fleuroselect Novelties or Gold Medal winners.
The Fleuroselect Gold Medal is awarded to innovative varieties that clearly surpass the limits in breeding and beauty. This symbolises excellence in breeding.
Many awarded varieties are widely supported and distributed by Fleuroselect members. The organisation also promotes the winners by way of press releases and displays at trade fairs and in gardens all over the world. Professional growers and hobby gardeners all over the world recognise the Fleuroselect awards as certificates of exceptional merit.
- Additional Information
Average Seed Count 50 seeds Seed Form Natural Family Asteraceae Genus Cosmea, Cosmos Species bipinnatus Cultivar Cosimo series, Collarette Synonym Cosmea bipinnata Common Name Semi-Dwarf Mexican Aster Hardiness Half Hardy Annual Flowers Red and White Natural Flower Time May to August Height 60cm (24in) Spread 40cm (16in) Position Needs full sun to flourish Soil Lean, well drained, sandy soils. Time to Sow Sow indoors March to April, or sow outdoors April to May Germination 7 to 10 days at 20-30*C (68-86*F)