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Floricultura b.v. | Heemskerk - Assendelft | www.floricultura.nl
© Floricultura. Copying all or part of this text is permitted, providing this publication is quoted as the source. Although our information and recommendations are prepared with the greatest of care, there are always subject to confirmation.
© Floricultura 。這文本複製的全部或部份被允許, 提供這出版物被引述作為來源。雖然我們的資訊和推薦準備與最偉大關心, 有總依於確認。
Temperatures
Night-Day
Vegetative phase 26°C-28°C(*盆苗株生長最優*)
Cooling at least 18°C-20°C(*催花梗100%成功*)
Flowering phase 20°C-23°C(*花期最長, 不斷結苞*)
(Depending on light)
Light Paphiopedilum cultivation does not require high light intensities. The best growth and flowering results are obtained by exposing the crop to moderate light intensities from 10,000 to 15,000 lux. High light intensities usually mean higher temperatures and, consequently, a lower RH. This is an essential point that should not be ignored. Paphiopedilum grows best from August to late in October when the natural RH is high. Shading and whitewashing have to be done from spring through autumn to prevent high temperatures. Certain kinds of shading compounds keep excess heat from penetrating the greenhouse whilst admitting more light. Cool wet summers are ideal for Paphiopedilum production but dry hot summers can be a problem. Growth lighting is not necessary but will contribute to growth during the winter. Light intensities plantlets 5,000 - 6,000 lux green-leafed varieties 10,000 - 12,000 lux variegated-leafed varieties 8,000 - 10,000 lux RH Providing the proper humidity level, the optimum ranging from 65 to 80%, is important for good growth and flowering. Maintaining the recommended levels 24 hours a day is not necessary. Whitewashing and shading are necessary. Humidification or the use of roof sprayers will greatly improve the greenhouse climate. When considering expenditures/income, roof sprayers are a better investment. The biggest problems occur most frequently when humidity drops too suddenly. Values exceeding 80% are acceptable and will not result in problems provided that heating raises the temperature slightly simultaneously with ventilating to provide air circulation and thus sufficient dehumidification. Note: A low RH on sunny days, particularly in the spring, slows growth. If the crop is observed closely, it can be noted that the leaves roll up and take on a drab colour. RH Between 65 and 80% Greenhouse systems A company will have to have at least two (and preferably 3) sections to produce Paphiopedilum as pot plants. Vegetative phase: (1) varieties with variegated leaves/multiple flowers (If only two sections are being used for this crop, the vegetative phase of green-leafed varieties can take place in the section accommodating varieties requiring warm temperatures during their flowering phase) Flowering phase: (2) green-leafed varieties. (3) varieties requiring a warmer greenhouse climate: those with variegated leaves/ multiple flowers Benches/mobile containers Production takes place on benches or mobile containers with an open bottom that can be made of various materials. Producing Paphiopedilum as pot plants cannot be done using ebb-and-flood or other closed-bottomed systems since this will always result in losses due to Phytophthora and Pythium. Heating The heating system used in the cooler section has to realise a minimum temperature of 16°C at night and 18°C during the day, regardless of outside temperatures. The warm section has to realise a temperature of 23 -25°C during the day and 20°C at night. Light Light plays an important role in Phalaenopsis production. During the vegetative phase, plantlets require exposure to at least approx. 4,000 lux (after this phase, up to 6,000 lux). Higher light intensities slow growth and result in leaf discoloration. For commercial production, this means that the roof of the greenhouse has to be whitewashed more than once to keep it coated from late February until mid-October and that one or two shade cloths will be needed to exclude excess light during this period. Growth lighting used in the autumn-winter period will improve conditions during the vegetative phase. After about six months of vegetative cultivation, most plants will be large enough (4 mature leaves) to be transferred to the spike initiation and flowering phase section. For spike initiation, it was formerly assumed that the crop had to be exposed to a minimum light intensity of 4,000 lux but no higher than 6,000 lux, but practical experience and trials have shown that light intensities from 7,000 to 8,000 lux provide excellent spike initiation and flowering results. Note: the costs of investing in higher-capacity lighting will not outweigh the benefits of slightly higher yields. The maximum daylength for Phalaenopsis production is 14 hours. Using growth lighting to extend the daylength beyond 14 hours will result in a lower rate of growth and a red discoloration of the leaves. Light intensities 4,000-6,000 lux is recommended during the vegetative phase growth lighting (4,000 lux) during the winter for at least 12 hours/day target range is 7,000-8,000 lux in the greenhouse during the flower initiation and flowering phase RH Providing the proper humidity level, the optimum ranging from 50 to 80%, is important for good growth and flowering. Values temporarily exceeding 80% are acceptable and will not result in problems provided that measures are taken to provide sufficient dehumidification. This can be realised by simultaneously heating and ventilating to maintain sufficient air circulation in the greenhouse. If the RH drops below 50% for only a short period, humidification will not be necessary. Maintaining the recommended levels 24 hours a day is not necessary. The biggest problems occur most frequently when humidity drops or rises too suddenly. Major changes in the RH due to an excessive rate of ventilation or uneven heat distribution increase the chance of loss due to a bacterial disease (Pseudomonas). RH between 50 and 80%. Greenhouse systems Sections A company will have to have at least two sections to produce Phalaenopsis as pot plants. The vegetative phase section where the plants will remain for approx. 6 months. The spike initiation and flowering section where the plants will remain for approx. 5 months. Under optimum production conditions, the proportion of space required for vegetative versus flowering phase will be 45:55. Grading and processing are usually conducted in the same area accommodating the plants during their flowering phase. Benches/mobile containers Production takes place on benches or mobile containers with an open bottom that can be made of various materials. We discourage the use of ebb-and-flood systems. Heating The heating system has to have enough capacity to keep the section being used for the vegetative phase at a temperature of at least 27°C day and night whilst maintaining the minimum temperature in the section being used for the spike initiation and flowering phase at 20°C during the day and 18°C at night, regardless of outside temperatures. Temperatures must not be any lower than these values! Shading system A shading system is required for both saving energy and reducing excessively high light intensities. Some companies have a double shading system to maintain even better control: one screen with an open weave to be used as the main shade cloth and a lighter one with a closed structure. Note: an external shading system offers a good way to cultivate at a cooler temperature without whitewashing. CO2 system A CO2 system is unnecessary. Phalaenopsis is a CAM plant that absorbs CO2 primarily at night. Growth lighting Growth lighting is necessary during the flowering phase in order to achieve the required light intensities during the winter months. It also provides advantages during the vegetative phase, primarily in regard to root development. The lighting system must have a capacity of at least around 4,500 lux. Providing up to 7,500 lux can result in improved spike initiation, e.g. a higher percentage of double-spiked plants. Note: it is not true that more light automatically has a positive effect on the crop. Besides the fact that more light will affect plant temperature and greenhouse climate (and this will require careful monitoring and making the right responses when necessary), higher light intensities do not always provide an economic advantage. Air-conditioning system Many companies have an air-conditioning system to ensure achieving a night temperature of 18°C during the summer period for good spike initiation. The daytime temperature must rise as little as possible. Having such a system makes it much easier to maintain the schedule for realising flowering in November/December, regardless of a possible a hot summer. The capacity of such an air-conditioning system will have to be 25 Watt/m2 of greenhouse space, which under Dutch conditions is equal to around 100 Watt/m2. Some companies have installed higher-capacity systems (up to approx. 150 Watt/m2) with the idea of being able to maintain greenhouse temperatures of 20°C even during an extremely hot summer. Other less expensive solutions can sometimes be devised. In hot regions (e.g. the Mediterranean ), daytime cooling can be realised by a pad and fan system with air-conditioning used at night. Here again, the use of these systems to control temperatures makes it easier to maintain a schedule of flowering. The necessity of these systems depends somewhat on the company’s location; even in a single country, conditions found in various regions can differ. It would also be possible to consider using a combination of these systems, possibly supplemented by roof sprayers or an external shading system. Overhead watering is necessary. Some companies use a boom system. Water distribution must be even and offer the option of control per bench or container. Greenhouse systems various sections for the vegetative, cooling and flowering phases in a ratio of 2:3 mobile benches/containers with open (wire) bottoms and high-capacity heating pipes underneath Sprinkler circuit with fertiliser proportioner for 2 tanks shading system, possibly combined with energy-saving thermal screens growth lighting: at least 4000-5000 lux recommended cooling section (15% of space), possibly with air conditioning system ■ ■ ■ ■ ■ ■ Floricultura b.v. | Heemskerk - Assendelft | www.floricultura.nl © Floricultura. Copying all or part of this text is permitted, providing this publication is quoted as the source. Although our information and recommendations are prepared with the greatest of care, there are always subject to confirmation. Water Water is one of the most important factors in production. Only rainwater or reverse osmosis water is suitable. Ultimately, any other kind of water will result in production problems. Provide enough water storage capacity. When using a small tank with a reverse osmosis system, the minimum water requirement should be calculated as being 15 litres/m2/week. Temperature of irrigation water Vegetative phase: the minimum temperature for irrigation water is 25°C . Flowering phase: the minimum temperature for irrigation water is 20°C . Warmer temperatures result in no problems as long as the water is kept below 25°C . Desired temperatures can be achieved by using a counter-flow system. Water rainwater or reverse osmosis water minimum temperature: vegetative phase > 25°C ; flowering phase ± 20°C maximum Cl: 50mg/l maximum Fe: 2mg/l maximum hardness: 3°KH Production procedures Delivered in flasks: Plants are delivered in plastic flasks directly from the laboratory. Upon receipt, they must be deflasked into a seedling tray filled with a mixture such as 90% bark and 10% sphagnum (possibly supplemented with some Perlite). After approx. 6 months, the plants can be transplanted into 12-cm pots. Delivered in seedling trays: Plants delivered in seedling trays have a leaf span (tip to tip) of 10/ 15 cm . Production starts by transplanting the seedlings from the seedling trays into final transparent 10/12-cm pots. The pots have to be transparent in order to promote good rooting. Various organic mixtures with good drainage and air retentive capacities can be used. The basis for such a mixture is usually finely textured bark supplemented with some sphagnum, coir, peat fibre or chunks of peat or pieces of coconut shell. Each substrate has its own character with regard to providing water and fertilisers. The plants should immediately receive water and nutrients by means of overhead watering. Hand watering is sometimes necessary and is also a good way to monitor the crop. Irrigating is done every 4 to 7 days depending on substrate and climate. As soon as the plants have 4 mature leaves, they can be transferred to the spike initiation and flowering phase section. (This transferring is usually done in two stages due to differences in plant size). Plant distribution in this section will be approx. 32–36 plants/m2 (about half the number/m2 than in the section used for the vegetative phase). Spikes should have been initiated after about 6 weeks. It will then be about another 12-14 weeks before the plants are ready for delivery, the exact number depending on the season and the variety. Substrate Consisting of well-draining organic mixtures, e.g bark, pieces of coconut shell or sphagnum. Proportions: at least two-thirds coarse material such as bark or pieces of coconut shell, and one-third absorbent material such as fibre peat, sphagnum, etc. Commonly used in the Netherlands : bark chips measuring 0.6 – 1.2 cm , and 3 or 4 kg of sphagnum/m2. ■ ■ ■ ■ ■ ■ ■ Floricultura b.v. | Heemskerk - Assendelft | www.floricultura.nl © Floricultura. Copying all or part of this text is permitted, providing this publication is quoted as the source. Although our information and recommendations are prepared with the greatest of care, there are always subject to confirmation. Use of space Plants/net m2 Period Need for space in % Potted in 12-cm pots 64 25 - 30 weeks 45 Cooling 32 6 - 7 weeks 15 Spike initiation -> flowering 25 12 - 16 weeks 40 Yields Yields in a modern facility using 84% of its space (as realised by mobile containers or mobile benches) and following proper cultivation methods will be 35 to more than 40 plants/m2 of greenhouse space/year. Using fixed benches results in a reduction of about 20%. Factors affecting yield are variety (multiflora/standard/grandiflora), rate of growth and percentage of loss. As a rule, the percentage of loss is between 5 and 10%. Note: Automated companies with grading systems used during the flowering phase can easily produce 50 plants/m2. Labour requirement The labour requirement is 1100 to 1500 m2 /worker/year depending on the degree of mechanisation and percentage of double-spiked plants. Yield 35 - 45 plants/m2 of greenhouse with an 84% use of space. Yield depends on rate of cultivation, percentage of loss and capacity for cooling. Temperatures As a rule, the target temperatures depend on the two phases: 1. During the vegetative phase, temperatures must be at least 26°C at night (maximum of 12 hours) and 27 -28°C during the day. Temperatures lower than 26°C will automatically result in premature spike development. 2. During the spike initiation and flowering phase, temperatures must be 18°C at night (maximum of 12 hours) and 20 -22°C during the day for at least 6 weeks. During the autumn and winter, maintaining a temperature of 16°C at night and 18°C during the day promotes spike development. If it is possible to arrange for a separate section for the flowering phase, the plants can then be maintained at a temperature averaging 1 -2°C higher than temperatures maintained during spike initiation. The advantages are a small improvement in quality and a shortening of the flowering phase. Temperatures lower than 18°C at night will lead to slowed growth rate and leaf discoloration or even bud drop. This method allows the grower to follow a good yearly schedule. Because we can deliver plants on a monthly basis, plants can also be potted up every month and be transferred to the spike initiation and flowering phase section every month. This means that growers can deliver flowering plants year round. Temperatures Night Day Vegetative phase 26°C 28°C Cooling at least 18°C 20°C Flowering phase 20°C 23°C (Depending on light) Floricultura b.v. | Heemskerk - Assendelft | www.floricultura.nl © Floricultura. Copying all or part of this text is permitted, providing this publication is quoted as the source. Although our information and recommendations are prepared with the greatest of care, there are always subject to confirmation. Fertilising Fertilising and irrigation are done simultaneously. The composition of fertilisers depends on the season of the year and the growth stage of the plants. Although either simple and/or compound fertilisers can be applied, working with compound fertilisers is usually much more practical. For the vegetative phase, a combination of calcium nitrate, Plantprod or Peters 20-20-20 and magnesium sulphate in a ratio of 2:6:1 would be a fine combination that could be supplied by a 2-tank system. During the winter period, part of the 20-20-20 can be replaced by a compound 17-5-34 or 18-5-35 fertiliser to reduce the N. Spike initiation and flowering phase: always adjust the N as indicated above during the winter period. This correction can also be required during the summer under extremely hot conditions since the percentage of N in the standard solution will be too high if temperatures exceed 27°C . If not corrected, foliage will become too lush. Standard fertilising using a fertiliser with an EC of 1.0 is the normal procedure. Depending on growing conditions, the EC can be adjusted to range from 0.8 to 1.2. These are also the values in the drainage water. The pH level should be monitored carefully. If too low, the solution is to apply ammonia and/or urea after having added Dolokal to the substrate. Depending on the materials used, Dolokal should be applied at the rate of 3 kg /m3. Fertilising 20-20-20 + CaNO3 + MgSO4 (6:2:1) 1 gm /l or and EC of 1.0 vegetative phase programme, possibly involving a reduction of N vegetative phase programme during winter: 17-5-34 Programming flowering Programming flowering Cool period Flowering period April - May August - September May - June October - November July - August December - January September - October February - March December - January April - May Diseases and pests With sound cultivation and sufficient control of the most significant enemies, the use of chemical control agents will be more an exception than a rule. It is important to start using biological control measures immediately following potting to control fungus gnats. Once this has been done, followed by monitoring, other problems are rare. Possibilities, however, include: Bud drop during autumn/winter resulting from too little light or poor roots California thrips produces symptoms similar to those resulting from tomato spotted wilt virus Erwinia/Pseudomonas weak plant development due to excessive nitrogen, high RH, little ventilation. Remove infected plants before each round of irrigation. Snails/slugs wet substrate, cold water, high EC Mites misshapen immature leaves Thrips misshapen leaves/flowers Brevipalpus red mite, discoloration on undersides of leaves Scales/mealybugs found on undersides of leaves, grey spherical scales or slow-moving pink or orange bugs dusted with wax that are found in clusters in leaf axils Fungus gnats slows growth rate, particularly when feeding on young plants; can be controlled effectively by Hypoaspis White worms larvae of flies feed on root tips in wet substrate Caterpillars feeding damage to flowers and leaves Galumna mites glossy, spherical mites that damage flowers or immature leaves It would be best to consult an expert with regard to which chemical control agents to use and what the application dosages are. ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■
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