oronia B Product: Boronia Botanical name: Boronia heterophylla and hybrids Cultivar: B. crassipes × B. heterophylla ‘Lipstick’ Quality specifications for Australian wildflowers Product: Product: Cultivar: Cultivar: name: Botanical B. crassipes × B. heterophylla B. × crassipes B. Low winter night temperatures (6–15 °C) are Boronia Boronia is a filler product grown for its dainty, small, 4-petalled flowers densely clustered along needed to initiate flowering (low temperatures optimise the speed of flower development and the stems. Boronia heterophylla is the main the number of buds initiated, while warmer species grown commercially for cut flowers. temperatures may lead to flower abortion). Boronia heterophylla heterophylla Boronia It is a small woody shrub endemic to WA. Several Boronia needs deep, well drained, moist soils to cultivars and hybrids are available with superior grow well. Plants have shallow root systems and flower features and an extended colour range, from need to be protected from hot and dry conditions white and lemon, pale to hot pink, to deep blackish by windbreaks and well irrigated during the purple (‘Purple Jared’). Both flowers and foliage warmer months when actively growing. Growers are aromatic. Indeed, Boronia megastigma (brown need to ensure that plants are well irrigated and boronia), grown for its unusual brown flowers, is an fertilised from flowering through to autumn to important source of essential oils. maximise stem length at harvest. Grow-through at the stem tips can be a problem. Careful ‘Lipstick’ has slightly scented, vibrant pink, bell- management of crop nutrition in the lead-up to shaped flowers 8–10 mm long, held on short flowering may help to minimise this. Stems are pendulous stalks. pruned back to 35 cm at flowering to maximise the Boronia has a long history in cultivation as an following year’s crop (cutting stems back too far ornamental plant: B. megastigma was introduced will kill the plant). and hybrids and ‘Lipstick’ into Britain in the 1840s; and bush-picked boronia Plants are susceptible to nematodes and a range has sold since the 1800s. Other boronias have to of root diseases caused by the fungi Phytophthora, date been limited in their floriculture potential Pythium and Rhizoctonia. Foliage can be affected owing to difficulties in propagation. by rust, and flowers are susceptible to botrytis. Plants will produce marketable harvests within Some markets, such as the USA, currently do not 12–15 months of planting but have a relatively short accept flowers or plants belonging to theRutaceae economic life (typically 5–6 years). family, which includes Boronia and Crowea. In Australia, the main growing areas are the south- Water stress during or after harvest reduces quality. west of WA, the south coast of NSW, central Victoria Boronia needs to be moved quickly from the field and the east coast of Tasmania. Overseas, boronia is to a cool packing shed. Stressed stems wilt quickly grown in several countries, including New Zealand, and flowers shrivel. the USA (California) and Israel. Overmature flowers tend to close up again, making it difficult to distinguish between immature and overmature stems. When overmature, ‘Lipstick’ flowers tend to turn white. Boronia is very sensitive to drying out. Pick straight into water in the early morning, maintain hydration and quickly cool the flowers. Handle carefully to minimise flower drop. Flowering season: September–October, depending on locality. The flowering season in any given locality is short, typically 2–3 weeks. Typical vase life: 7–11 days (poorly handled Boronia may last for only 3–4 days). Export can reduce the vase life, especially if the transport conditions are not cold, the product has dried out, or transport takes too long. Other products to which this specification can be generally applied: Other Boronia species, cultivars (e.g. ‘Moon Glow’ and ‘Cameo’) and hybrids such as Left: Boronia is available in a range of colours, e.g. ‘Purple Jared’ ‘Purple Jared’ , and superior selections, including ‘Stella’ , Cascade’ and ‘Purple Rain’ Right: Typical bunches look like this Product: Boronia STGSF A E O OPENING The stages shown apply to the product at market entry. Pay attention to the weather, time of year, and mode and duration of transport, because the flowers will continue to open during transport. You must consult with Stage 1 your target market Stage 2 Stage 3 Immature stage, unacceptable to ensure that the Early stage, preferred by only Prime stage for export and to markets: flower buds flowers arrive at the a few markets, e.g. for export: domestic markets: 50%–70% immature and closed (will not desired stage. most flower buds still closed of flowers open open after harvest) COMMON DEFECTS Common defects to avoid at market entry: n L eaf and flower drop n S parse flowering or missing flowers n O vermature (faded to white) flowers n W ilting stems n D ried-out flowers n D amaged, yellow or discoloured Grow-through Wilting flowers – avoid by Poor-quality foliage leaves harvesting at correct maturity and by avoiding water stress after n P resence of picking diseases (e.g. rust), insects or feeding damage n M issing sections of foliage n G row-through Sparse flowering at stem tip Broken stem ends – trim evenly Flower drop – do not market; Flowers bleached owing to – discard before marketing avoid by treating bunches with overmaturity – discard anti-ethylene silver solution Stage 4 Stage 5 Late stage, suitable for only Mature stage, unaccepted by some domestic markets: all many markets: flowers closing flowers open but some starting again and turning white as to turn white with age they age For comparison: just right and slightly Flower development from immature bud immature stem at left to overmature where flower closes up again as it ages Rust-infected shoot (left) compared with healthy shoot Insect-damaged flower Buds at stem tip have not Rust disease on leaves Close-up of rust-infected shoot Bleached and browning flowers – discard stem if a large developed – discard – discard; avoid by applying – discard number of flowers are appropriate fungicide treatments damaged before harvest Product: Boronia FLOWERS GRADING AND BUNCHING Appearance Flower colour clear and uniformly deep pink. Grading Reject any contaminated stems. (‘Lipstick’) True-to-type of the cultivar ‘Lipstick’. Sort stems according to flower maturity, length and Flowers clustered densely and massed evenly along and thickness. around the entire marketed stem. Minimum leaf visible. Stem length According to market demand. When to 50%–70% of individual flowers open at the base of the Bunching The number of stems per bunch varies, and is harvest stem, and those at the tip showing colour (immature determined by their length and by market and buyer flower buds will not open after harvest). requirements. Avoid harvesting when flowers are wet. Presentation is important. Stay consistent for the grade and make all bunches the same. Damage Not faded. Use 1 tie near the base (3 cm from bottom). No wilting. No flower drop. Especially for export, stems should be approximately the Minimum number of flowers deformed or damaged same diameter within a bunch, with the ends aligned. (including mechanical damage). Stems per Different markets require different bunches – broadly: Contamination Product free of grit and soil, weeds or weed seeds, living bunch or dead insects, and signs of insects or spiders, such as Stem length (cm) Av. no. of stems per webbing. bunch (typical bunch weight, g) Pests and No insects, insect damage or disease. diseases 80 10 (400) LEAVES 70 10 (400) Appearance Fresh, mid green and crisp. 60 10 (350) 50 10 (250–300) Damage Not dull or wilted. No leaf drop. No yellowing. Minimum leaf damage or blemish. 40 10 (250–300) Minimum evidence of pests, such as webbing, and disease. No evidence of rust. Sleeves Avoid sleeves, which increase humidity and favour Free of visible chemical residues. botrytis. STEMS HOLDING AND STORAGE Appearance Well branched and balanced. No irregularly branched Cooling Effective cooling soon after harvest is important to stems. retaining quality and maximising vase life. The preferred Rigid and strong enough to support blooms, without option is: being too woody and bulky. • Cool, process, cool – for example, remove field heat Bend <15°. by cooling flowers immediately by placing in a cool No obvious grow-through, where the shoots at the stem room at 2–4 °C in buckets of postharvest solution, tip grow through the flowers: maximum 3 cm tip growth process flowers (bunch, grade), and then cool to 2–4 beyond flowers (but soft tips will wilt after harvest). °C by either forced-air cooling (if boxed) or holding overnight in a cool room. Leaves are usually stripped from the lower 8 cm – check customer requirements. Forced-air cooling of packed flowers is ideal for large volumes of product. Neatly cut end. Length According to market demand. Temperature Hold in a high-humidity cool room (95%) at 2–4 °C for and humidity up to 2 days, but preferably much less. RECOMMENDED HANDLING AT HARVEST Disinfestation Do this before a long (overnight) anti-ethylene pulse (see ‘Common or During harvest, it is critical to minimise drying out and exposure to heat. It is postharvest after a short pulse (room temperature). better to harvest early in the day, as long as the stems are not wet (which can problems’ below) encourage botrytis). Preferably pick into clean potable water, ideally with added registered biocide or a reputable commercial postharvest solution, and transport promptly to a cool, shaded packing shed (within 30 minutes after picking). Handle stems carefully, as flowers fall off easily. HOLDING AND STORAGE cont’d COMMON POSTHARVEST PROBLEMS Refer to Postharvest Manual* for general advice. Anti-ethylene ‘Lipstick’ and other B. heterophylla selections are ethylene treatment sensitive.