Senecio for Cut Foliage

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1 Cut Foliage Fact Sheet No. 7 Senecio for Cut Foliage Introduction The New Zealand native broadleaf evergreen shrub Senecio also called Brachyglottis with the common name daisy bush is a member of the large Asteraceae family and belongs to the genus Brachyglottis. It is a tough little evergreen shrub with oval, hairy, grey leaves and cheerful, bright yellow, daisy-like flowers borne in branched clusters in June and July. This lovely shrub can withstand strong winds and salty air which makes it ideal for coastal areas but it also grows well further inland and is quite hardy. It is resilient, relatively trouble-free and fast-growing. It is extremely adaptable to almost all soil types. The grey leaves, with silvery white felty underside, is favoured by the foliage market. The stems are used as fillers in mixed flower bouquets or in some cases form the centre piece in an arrangement. There is an increasing export market to specialist bouquet companies in the UK and Holland, who in turn supply the major supermarkets and other retail outlets.

2 Page 2 Site & Soil Requirements The site must be well sheltered from prevailing winds. While a south-facing aspect is desirable, it is not essential. The south east of Ireland appears to be a very suitable production area. The site must be protected from rabbits (if a problem) and be accessible. The soil should be deep and well drained. Aim for a ph of 6.5 and a good balance of phosphate, potash and magnesium. A soil analysis is recommended prior to cultivation. Contact your adviser for specific recommendations on base fertilizer dressings, following soil analysis. Species/Cultivars The main species grown for foliage is Brachyglottis greyii. A new cultivar Drysdale (pictured) which has a distinctive serrated leaf is showing promise and is currently in trial with a number of others which are showing potential. Plants Plants can be raised from cuttings which are taken in the autumn and good bushy 9 cm plants should be ready for planting out 18 months later, in the spring period.

3 Page 3 Soil Preparation It is critical that the site has first been cleared of perennial weeds by spraying off, using a mixture of Glyphosate (Roundup) and Carfentrozone- Ethyl (Spotlight Plus). Young plants (liners) are planted on the flat in most cases following the standard cultivations of ploughing and rotovation. The species does not like wet soil conditions, so if necessary, planting on a raised bed or ridge may be warranted if soil is prone to holding water in wet seasons. Plant density Planting is carried out in rows 2m apart, with plants 1m apart in the row. This gives an overall plant density of approximately 5000 plants per ha (2000/ac). Alternatively you can plant at closer rows (1.5m) but it is recommended that a 3m wide tramline should be left every meters, depending on tractor and sprayer widths, to facilitate tractor operations and ease of harvesting. When higher density systems are used, a more intense level of plantation management is required. Weed Control It is very important to keep plantations free of weeds, particularly in the first few years of establishment, after which the developing crop canopy smothers out most non-perennial weeds. While the use of mypex or a plastic membrane on the planted row in conjunction with a mowed grass or cultivated strip between rows is

4 Page 4 sometimes recommended as a weed control measure, the most common method is the use of carefully chosen residual and selective contact herbicides. The choice of herbicides to maintain clean plantations depends on the weed spectrum, but products such as Stomp Aqua (pendimethalin), Ronstar liquid (oxadiazon), Venzar (Lenacil) and Kerb 50 W (Propyzamide) have label recommendations for overall or directed application. Spot treatment of perennial weeds with Roundup or hormone weedkillers is sometimes necessary in foliage plantations, even when crops are well established. Safety, legal and economic considerations dictate that herbicides must be used with great care in following the manufacturer s recommendations of timing, dosage and accuracy of application. Contact your adviser for the most suitable method of weed control for your site and up-to-date herbicide recommendations. Nutrition There has been no experimental work carried out on the nutritional requirements for Senecio when grown for cut foliage. The use of nitrogen will result in good growth response. Apply up to kg/ha nitrogen in the Spring in split applications. Magnesium is an important element and foliar applications are necessary during the growing season. Consult your adviser for recommendations as site requirements can vary.

5 Page 5 Pruning If the species is left un-pruned it gets untidy and the foliage looses its good looks and flowering can take from the development of good strong stems desirable for the cut foliage trade. For that reason, annual pruning is necessary once the plants have established from the second year onwards. Aim to prune the plants back to within 40 cm of ground level annually. Trials work is in progress to determine the optimum timing and regime for pruning Senecio. Picture shows the effect of pruning 1 year old plants. Un-pruned plants with prolific flowering on the left compared to cutting back to within 40cm of ground level on the right resulting in marketable stems.

6 Page 6 Pests and Diseases Senecio is relatively trouble free from pest and disease issues. Monitoring for the presence of the following pests is important early in the season. Caterpillars of the caranation tortrix (Cacoecimorpha pronubana) can be problematic and will have to be monitored for during the season. Insecticide treatments are justified during the growing season. Slugs have been found to be problematic particularly in wet seasons with damage seen from early spring right through to the Autumn. Monitoring and test baiting is recommended and treatment with a Methicarb based product is generally effective if problems are encountered. Rust can sometimes be found on older leaves but seldom warrants fungicidal treatment. Harvesting and Processing Senecio is normally harvested from October through to April. All harvesting is done using a hand held secateurs. Generally well-furnished stems, 45 to 55 cm in length are carefully selected for

7 Page 7 quality of leaf and shoot balance. The first stems are fit to cut in the second growing season with full cropping potential being reached from the third and fourth year onwards when up to 100,000 stems per hectare can be harvested per annum. Cropping can continue for a further 10 years if plantations are well maintained and managed. In most cases all grading is carried out in the field. Stems are bunched in 10 s and then transported to the packing shed where they are stood in water overnight and kept cool prior to packing. The processing operation consists of tying the 10 stem bunches in bigger bundles of 150 stems and placing in a bucket containing 1 inch of water. These buckets are then placed on a Danish trolly on which they are transported. Costs & Returns Some stems are harvested in the second year with full economic yield (up to 100,000 stems/ha) not reached until the third/fourth year. The crop continues to yield for a further years if managed correctly. For a crop grown on a bare soil system, from an initial investment of 3000 per ha, a gross return of 6000 per ha is achievable from the fourth year onwards. Net return depends on the grower s involvement as most of the annual cost is labour (maintenance & harvest). Even when labour for harvest is included a net return of 1750 to 2000 per ha is achievable. Further detailed information is available from Teagasc Cut Foliage Specialist: Andy Whelton, Teagasc Horticultural Development Unit Tel:

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