Matthiola incana, 'Avalanche'

Matthiola incana 'Avalanche' is a variety of the traditional tall stocks that are grown for the floral industry. This marvellous cut flower strain reliably produces large, fragrant, double flowers on densely populated panicles on strong, single stems. The pure white flowers are long lasting and magnificently fragrant with a sweet and spicy clove scent, this variety is particularly suited for beds and for cutting for the vase.
This tall variety grow to a height of 75cm (30in) and produces a high percentage of double flowers that can be selected based on leaf colour. Sow anytime from January to July for flowering April to October. From sowing to flowering takes around 90 days.

Stocks can be sown early in spring to give a good summer flower display or can be treated as biennials. Seedlings started inside in October will have the flowers ready for Valentine’s Day. The extra trouble of overwintering the plants is compensated by the showy spring floral display. If seed is sown in succession, they will provide continuous flowering over spring and summer. Stocks also make magnificent winter flowering pot plants for the cold greenhouse.
Eminently suitable for cutting, a fragrant bed of stocks in the garden makes spring and early summer delightful. There is very little to match Stocks for their fragrance, flower displays and ease of growing.

Selecting plants:
While the commercial cultivation of double flowered stocks is fairly complicated, there is a simple method that the industry uses to be able to select double flowered forms. You can have a go yourself and select them to suit your own taste.
When the seedling leaves have formed and the plants are large enough to be pricked out, allow the temperature to fall and the seedlings leaves will show a marked difference in colour. The leaves will be either dark green or light green, the difference in colour lasts for about 14 days.
Prick out into individual pots to grow on, keeping the light green seedlings separate as they represent the 100% double flowers.

Sowing: Sow in spring to early summer or sow in late summer / autumn.
Matthiola can be grown either as an annual with seeds sown in March to April or grown as a biennial, with seeds sown in July to August. Seeds can be sown indoors in pots or can be sown directly outdoors where they are to flower
They can be grown as an annual and planted early in spring, for flowering in late summer through autumn. Grown as a biennial, they can be planted later in the year to the end of October and overwintered to give flowers the following spring. Seedlings started inside in October will have the flowers ready for Valentine’s Day. The extra trouble of overwintering the plants is more than compensated by the showy spring floral display.
If seed is sown in succession, they will provide continuous flowering. Stocks also make magnificent winter flowering pot plants for the cold greenhouse.

Seed can be sown directly outdoors in spring, and in mild-winter regions they can be also sown in late summer/autumn. This later sowing will often produce flowers in winter as well as spring. (The plants will take moderate frost but will not set flower buds if the nights are very cold).
Sow in a good free draining compost, but do not exclude light, which is beneficial to germination. Germination usually takes 10 to 18 days at 15 to 18°C (60 to 65°F). Transplant indoor plants when large enough to handle and select double flowering seedlings at this time. Grow on under cooler conditions at about 10 to 15°C (50 to 59°F). Gradually acclimatise pot grown plants to outdoor conditions for 10 to 15 days and plant out 30cm (12in) apart after mid-May. Find a sunny position for them in well-drained soil.

Cultivation:
The plants need a position in full sun with moist well-drained soil, they will benefit from a light dressing of lime. The taller species will need staking and should be sited in a protected position where they will be sheltered from wind. Where winter rainfall is heavy, plant in raised beds for good drainage.

Harvesting Cut Flowers:
Matthiola are known by florists as Stocks, they are valued for their spicy sweet perfume and perfect for cut flower arranging.
The flowers open from the bottom of the spike upwards. To harvest, pull up the entire plant, roots and all, and then wash all the dirt off the roots in a big bucket of water. Leave the plants in water and cut the stems shortly before arranging.
Flowers can be dried by hanging in a dry spot out of direct sun. The deeper shades hold their colour best. The fragrance also endures.

Plant Uses:
Cottage/Informal Gardens. Flowers Borders and Beds, Coastal. Cut flower arranging.

Origin:
Matthiola is a genus of 55 species. Matthiola incana is a short-lived perennial, native to the lands along the Mediterranean from Spain to Turkey and south to Egypt. It is a plant of rocky cliffs and harsh dry land.
In the US, Jefferson listed "Gilliflower" as a hardy perennial in 1771. This Mediterranean flower is usually grown as an annual or biennial today.
Used extensively by the commercial floral industry because of its spicy scent and long lasting blooms, Matthiola incana may have been commercially cultivated as far back as the Roman Empire. An English garden favorite since Elizabethan times, Matthiola incana produces both single and double flowers and long grayish-green leaves. White is the most common colour, but Matthiola incana also grows in pink, red, yellow, lilac and purple.

Nomenclature:
Named for the 16th century Italian naturalist and physician, Pietro Andrea Matthioli (1500 to 1577) who first identified Matthiola incana. Imported into England immediately after its discovery and identification. It wasn’t until the 19th century that William Townsend Aiton identified it as a member of the Brassicaceae, the mustard family. Matthiola incana was bred extensively and soon became a favourite in English gardens.
Gerard wrote, "...a pleasant purple colour, and the others white...we have some that beare double floures, which are of divers colours, greatly esteemed for the beautie of their floures, and pleasant sweet smell."

Sea stocks, wallflowers and wall-gillyflowers are old English names. Gillyflower or gillofloure, as John Gerard spelled it in 1597, also referred to pinks and sweet williams. The Elizabethans called them "Stockgilloflowers" for their carnation, of gilliflower-like fragrance and woody "stock" or stem. Today, Stock is the vernacular for species of Matthiola and in particular, Matthiola incana
There is an annual variety named M. annua which will bloom quickly and has fragrant, double flowers. M. longipetala bicornis (Night-scented stock) is an annual that bears single pale violet flowers that emit a pervasive sweet scent each night.

Stocks were once grown for medicinal purposes, and a comment attributed to Pierandrea Mattioli that he grew these plants only for matters of love and lust, suggests the medicine had much to do with the scent.
Gerard had little respect for the medicinal use of stock. "...they are not used...except by Empericks (empirics, practicing medicine by intuition or experience) and Quacksalvers (vain pretenders to medical skill), about love and lust matters, which for modestie I omit."

For horticultural purposes, the stock, Matthiola incana has four cultivar lineages.
They may be treated either as annuals or biennials. If treated as annuals they give a fine late summer and autumn display. Treated as a biennial they will flower in spring.

The Brompton varieties. Robust, fast-growing, vigorous plants, branching and usually treated as biennials. One of today's most popular cultivars, the Brompton, was bred in the Brompton Gardens in London, site of the present day South Kensington museums. (Occasionally incorrectly spelt Brampton).

Intermediate varieties. Similar to Bromptons but are of a dwarfer habit.
Sometimes called "East Lothian" stocks, as they originated in southern Scotland.

Column varieties. Grown for the floral industry.
Plants have large flowerheads and are unbranched. They grow 60 to 90cm (24 to 36in) tall.

Ten Week Stocks. Fast growing, the Ten-week Stocks are usually grown as annuals and sown in spring to give a good summer flower display. Of the Ten Week line, there are a number of named series, some tall, up to 60cm (20in), and others dwarf, under 30cm (12in) and spread 15 to 25cm (6 to10in).