Bedding Plant Production & Management Practices PDF

87 Module 3 Lesson 3: Production and Management Practices of Bedding Plants Lesson Objectives: After completing this lesson, you are expected to: 1. Discuss the production management of bedding plants; and 2. Determine the wa...

87 Module 3 Lesson 3: Production and Management Practices of Bedding Plants Lesson Objectives: After completing this lesson, you are expected to: 1. Discuss the production management of bedding plants; and 2. Determine the water, light, temperature and soil requirements of bedding plants. Timeframe: 4 Hours Introduction In this module we will tackle on the importance of growing selected bedding plants as well as factors that will affect its growth and development. Likewise, general cultural management practices of these ornamental plants are also dealt with such as provision of proper nutrition and growing media, water, light and favourable environment that would favour optimum growth. Activity Let’s Check! List 5 bedding plants commonly grown in your locality. ANALYSIS Let’s evaluate! 1. Describe important features of bedding plants.  88 Abstraction (What you need to know!) Introduction to Bedding Plants Most bedding plants consist of fast-growing annuals and are generally propagated from seeds. They are mainly started under the more controlled condition of a sheltered environment. They are often grown in containers or raised in smaller pots in the nursery the subsequently transferred to more permanent planting in bigger pots, in basket, or on beds. Among the bedding plants produced in large quantities by local producers are Begonia (Begonia x semperflores-cultrum), Celosia (Celosia cristata, C. plumosa), Coleus (Coleus x hybrida), Cosmos (Cosmos sulphureus), Impatiens (Impatiens wallerana), Marigold (Tagetes erecta, T. Patula), periwinkle/Vinca (Catharanthus roseus), Petunia (Petunia x hybrida), Salvia (Salvia splendens), and Zinnia (Zinnia elegans). Seed Procurement and Storage Successful mass production of bedding plants starts with the procurement of quality planting materials. Seeds with more rapid and uniform germination should be obtained from reliable sources. Bargain seeds that are already old, not true to type, and with poor germination should be avoided. Good seeds, when not planted soon should be stored properly, that is, at low temperature and humidity, to minimize decline in viability and vigor. Seeds of many bedding plant species can be stored for one or more years at 0ºC to 5ºC or for shorter periods with 10ºC at 50 percent relative humidity. If the relative humidity is too slow, however, too much moisture may be lost, thereby affecting germination. For instance, Salvia and Vinca seeds may have reduced and have irregular germination if their moisture content goes below seven percent. Germination Media All germination media should be properly sanitized. A good medium should be well drained yet retain adequate moisture. The most readily available media with these features consist of cocopeat (coconut coir dust) and sand (3:1 v.v.) or sandy loam: coco peat: sand mixture (1:1:1 v.v.v.). The pH should be adjusted to 5.5 to 6.0. A good germination medium should be light (bulk density of about 26 kg per 0.028 cubic meter when wet). Sowing Sow seeds in rows or broadcast evenly on the medium surface before covering, for larger seeds, cover them with the medium to adepth of about half of the seed diameter. Water seeds thoroughly or place seed boxes under a mist system. If misting is not possible, you may cover the flat with a plastic film to keep the medium moist but not soggy. Lighting Some seeds are dormant at the time of sowing and this can be relieved by exposing the imbibed seeds to light. For instance, begonia, coleus, impatiens, petunia, and salvia should not be lighted continuously during germination. Some seeds like Impatiens should be exposed to about 500 feet candle light for 24 hours after inhibition of water, then germinated in darkness until seedling emergence, and subsequently transferred to light. Other seeds which germinate better when exposed to light before germination in the dark include begonia, coleus, nicotiana, petunia, and salvia. Others like centaurea and vinca germinate best in darkness while aster, celosia, cosmos, marigold, and zinnia germinate well, whether exposed to light or not, after imbibition. Temperature For many of the bedding plants mentioned, the best medium temperature for germination is between 20ºC and 26ºC. The range can further be refined for each genus or cultivar by actual trials.  89 Transplanting The seedlings are ready for transplanting after two to three true leaves have emerged (not the cotyledonary leaves). Delays in transplanting cause hardened and oversized plants that lack normal vigor after transplanting. If, for some reason, they cannot be transplanted, they should be placed in lighted refrigerated room or shelf at temperature below 10ºC and far longer storage at 5ºC to 7ºC for those that can withstand this temperature without chilling injury. Seedlings should not be transplanted too deep to minimize stem rot. Also, avoid placing weak and vigorous seedlings in the same flat. Before transplanting, seedlings should be sorted according to size and vigor so that uniformity of plants within flats or container is ensured. In the absence of environmentally –controlled greenhouses for raising plants to saleable stage, mortality rates can be reduced by hardening of the seedlings before transplanting. This is done by watering the plants at reduced rate or frequency or both so that the medium is maintained at the drier side. Light intensity is also gradually increased to the level of light existing in the location to which the plants are to be grown. The soil to which plants are to be transplanted should be moist but not saturated, at least for the first week. Also, fertilization is not recommended until after one week from transplanting. Care of Plants Up to flowering Subsequent plant growth up to flowering is conditioned by several factors particularly light, temperature, water, and nutrients. Light The three aspects of light important to plants are intensity, duration, and quality. Maximum light intensity is not always desirable for all phases of production. Young seedlings may be killed if exposed to excessive light. On the other hand, if light is insufficient, plants tend to be leggy and weak. Table 5.2 Daylength requirements of some bedding plants Long-day Short-day Day – neutral African Marigold¹ Celosia Begonia (fibrous) Petunia Coleus Dianthus Salvia¹ Cosmos Impatiens Marigold (African) Marigold (French)¹ Salvia Salvia Vinca ¹ Depends on cultivar Table 5.3 Categorization of bedding plants according to nutritional requirement Light Moderate Heavy Impatiens Celosia Begonia Marigold Portulaca Petunia Vinca Salvia Zinnia  90 For optimum development, the correct daylength should be provided. Table 5.2 shows the daylength requirement of the more common bedding plants.The relative needs of the different bedding plants are shown in Table 5.3. Some are relatively high feeder others are categorized as low feeder. It should be pointed out that temperature also influences the response of plants to daylength. For instance, at 12.8 ºC to 21.1ºC night temperature petunia behaves as a long-day plant. But a lower or higher night temperature, it behaves as a day-neutral plant. The quality of light reaching the lower leaves is altered (i.e., the red/far-red ration) when there is greater inter shading of plants due to closer spacing of highest plant density per unit area. Too much far- red relative to red promotes stem elongation. Temperature The temperature optima varies with the stage of plant development for a specific physiological process. For instance, for certain Impatiens cultivar, 24.4 ºC/18.9ºC day/night favor vegetative growth (i.e., higher rate of leaf unfolding, longer internodes, and thicker stems due to greater partitioning of carbon to the stems). For finishing, however, a constant 20ºC-22.2ºC day and night will result to reduced plant height but larger flower size due to partitioning of carbon in favor of the flowers. Species from warmer climates have higher temperature optima than those cooler or temperate climates. The temperature for plant height increase also decreases as plants age. Optimal temperature also varies with the time of the day. Higher day temperature tend to promote higher photosynthetic rates. Cooler nights decrease respiration or carbohydrate depletion. Combined warmer days and cooler nights would, therefore, promote higher gains in plant weight. Nutrition The rates and frequency of fertilization depends on the type of medium, frequency of watering, solubility of fertilizers, and nutrient requirements of plants. Fertilizer formulation need to vary from time to time to keep the fertilization program within the boundaries of five sets of nutritional specifications (pH adjustment; ammonium versus nitrate ration for growth control; phophorus requirement; and calcium, magnesium, and sulfur needs). It would be a mistake to follow one fertilizer program because it proved successful in one operation. BEGONIA (Begonia semperflorens) Begonia, unlike the tuberous begonias, are used as bedding plants. Grown under hiugh light intensity, it is propagated by seed but may be propagated by stem-tip cuttings to shorten the growing period. Plants are grown at 15.5ºC. if the temperature goes above 21ºC, especially on short days, the plants may remain vegetative.  91 CELOSIA (Celosia cristata and C. Plumosa) These are propagated from seeds and require a temperature of at least 18.5ºC. Celosia plumosa has a feathery plume-type inflorescence while C. Cristata has inflorescence that resembles a cockscomb. Among the low-growing cultivars are “Dwarf Empress,’”Kardinal,’ and ‘Jewel Box”. The taller cultivars include “Prairie Fire’, ‘Flordale,’ ‘Fireflow,’’Toreador,’ and ‘Yelloe Toreador’. The low-growing C. plumosa cultivars include ‘ Golden Gem’, ‘Crusader’, ‘Fiery Feather’. C. spicata, known as Wheat Celosia has silvery rose flowers borne in slender spires. The plants are taller and are thus suited as cutflowers. COLEUS (Coleus x hybrida) Coleus belong to the mint family. they are grown as bedding plants in shaded locations. They are popular because of their colorful foliage. Two new groups of coleus are the Rainbow and the Carefree Series. Coleus are tropical plants that prefer warm temperatures. Minimum night temperature is 15.5ºC. Most of the newer cultivars are grown from seed but can be propagated by terminal stem-tip cuttings. Cultivars in the Rainbow Series include the following: ‘Golden Rainbow,’ ‘Imp. Pink Rainbow,’’Pastel Rainbow,’ Pink Rainbow,’ ‘Red Rainbow,’ ‘Rose Rainbow,’ ‘Scarlet Rainbow,’ and ‘Velvet Rainbow.’ Cultivars in the Carefree Series include: ‘Carefree Golden,’ ‘Carefree Jade,’ ‘Carefree Pink,’ ‘Carefree Red,’ and ‘Carefree Mixture.’  92 Since the plant is mainly grown for its foliage, visual deterioration of quality of the foliage due to senescence can be delayed by removing the inflorescence as soon as they are formed. COSMOS (Cosmos sulphureus) Cosmos is a common bedding plant, particularly the dwarf sulphur cosmos, Cosmos sulphureus. The cosmos used as cutflower is lace cosmos, Cosmos bipinatus which may attain a height of about 3 - 5 feet. When propagated from seeds, seeds should be coveed for best germination at 21.1ºC- 22.2ºC under intermittent mist. Best growth at 15.6ºC-18.3ºC. Low fertilization is recommended. It is a quantitative short- day plant and at a daylength greater than 14 hours, flower development is delayed, Cosmos is also a heat- loving plant and grown and flowers well at 15.6ºC. As the plant matures, the need for short-days decreases. Thus older plants tend to flower more under long days. Plants with 6-8 pairs of leaves are mature enough to flower. The SD requirement can partially be substituted by a foliar spray with 100 ppm GA. IMPATIENS (Impatiens wallerana) v  93 Impatiens as bedding plants are grown in shady locations. They are grown from seeds or cuttings. Impatiens seeds respond quickly to moisture stress. Hence, seeds should be covered with the medium but light is needed for germination. Pre-exposure to light for 24 hours after seed imbibition is needed. Best growth after germination is at 18.5ºC. Growth is retarded if day temperature exceeds 27.5ºC. Ammonium fertilizer retard germination. Thus, using calcium nitrate helps prevent the development of ammonia problems. About 9-12 weeks after sowing, the plants are in bloom and ready for sale. If plants grow too tall, they can be pinched back. They will then branch and produce new growth which will bloom in 3-4 weeks. Impatiens is very sensitive to soluble salt levels. The salt level of the germination medium should be less than 70 mhos using the 1:2 dilution method of test extract preparation. The seedlings are more uniform when grown at lower salt levels. Fertilizers are applied at concentrations not exceeding 100 ppm N. Frequent applications of low nutrient strength solutions are preferred. There are about five series available, namely: Accent Series, Blitz Series, Deco Series, Showstopper Series, and the New Guinea Spectra Series. The ‘Accent Burgundy Star’ is a burgundy and white bicolor addition to the Access Series. There are now five bicolor selections in the Accent Series, plus a bicolor mixture. ‘Blitz 2000’ is a new and improved line of the largest flowering Impatiens in the Blitz series. The Deco Series is a new series of bronze-leafed Impatiens. The colors are bold and bright, especially the ‘Deco Rose’ and ‘Deco Violet’. The Decos are very versatile. They can be used as a bedding plant, hanging basket, or container cultivar. Flowers are excellent at 1.5 inches. The ‘Showstopper Cherry Flair’ is a new color in the Showstopper Series. It has a creamy white flower with a vivid carmine-rose streak down each of the bottom two petals. It is an excellent plant for hanging baskets. The ‘New Gunea Spectra Series’ is a large flower plant with diameters at 2-2.5 in. the foliage is excellent for window boxes, color bowls, and other containers. MARIGOLD (Tagetes erecta and Tagetes patula) The Tagetes patula (French Marigolds) arre generally shorter than the African Marigolds. Targetes erecta. The dwarf forms are excellent pot and bedding plants, while the taller ones are used as cutflower. Plants easily grow from seed. The best germination is at 21ºC-24ºC. Soon after germination, they should be maintained in cooler temperature, about 15.5ºC-16.5ºC, to produce bushier and heavier growth. Very often they are finished at a night temperature of 10ºC-13ºC. Long days promote vegetative growth while short days (9 hours) promote flowering. In the past, marigolds had a strong fragrance that many people found objectionable. The newer cultivars have a less pungent aroma, but still smell like Marigolds.  94 PETUNIA (Petunia x hybrida) There are five types of Petunia identified by modern common growers. These are grandiflora singles, grandiflora doubles, multiflora singles, multiflora doubles, and California giants. Grandiflora singles – This is the most common type, producing large number of flowers each measuring about 5 inches across. The supergrabdiflora or Cascade type Petunia is a popular mutation of the grandiflora type. It is an outstanding plant for hanging baskets, windo boxes, or any location where the long trailing branches can hang freely. Popular cultivars include ’White Cascade,’ Red Cascade,’ and ‘Chiffon Cascade.’ Grandiflora doubles – This type was the first to be offered as F hybrid seeds. The plants are 1 commonly grown in pots as specimens. These plants must be grown in warm locations and fertilized well for best growth and quality flowers. Multiflora singles - This type has many flowers per plant. They also mature faster than the other types, produce the most branches and flowers, and are available in the gretaest range of colors of all the Petunia classes. Among the more common cultivars include: ‘Checkers,’ ‘Comanche,’ ‘Mercury,’ ‘Paleface,’ ‘Plum Pudding,’ and ‘Sugar Plum.’ Multiflora doubles – This type has a smaller flowers that the grandiflora doubles. They are more compact in size and have greater number of flower in each plant. The flowers have ruffled edges and look like miniature carnation. The popular cultivars in this group include the ‘Tart’ Series, ‘Cherry Tart,’ ‘Plum Tart,’ ‘Apple Tart,’ ‘Peach tart,’ ‘Strawberry Tart,’ and “ Snowberry Tart.’ California Giants – This is relatively small group with flowers up to 4-6 in in diamater. It is used mainly as an accent in beds or bonders or as a flowering pot plant. Some of the cultivars in this group include the ‘Frolic Fluffy Ruffles,’ and ‘Ball Dwarf’ Giant No. 1.’ The culture of Petunias is similar to those of other bedding annuals. They are propagated from seeds. Petunia seeds are very small, about 285,000 seeds/oz. It is sown by broadcast on the surface of the germination medium and even when not covered, the small seeds easily fall into the spaces between the particles of the medium, Maximum germination is at 24ºC-27.5ºC. During germination, the medium must be kept evenly moist either by missing or covering with a plastic sheet to maintain a high relative humidity. The germination flats must be provided with artificial light (about 850 – 1000 fc). The light intensity could be provided by using two four-tube fluorescent light fixture mounted side by side, 6 inches above a three-foot wide bench. As soon as the seedlings have produced one or two pairs of true leaves, they are transplanted in coco peat-sand growing medium.  95 A quality crop is obtained if the grower is careful in following a schedule for fertilization, watering, and ventilation. As soon as plants are growing well, they should be fertilized with a 20- 20-20 analysis fertilizer solution to provide about 150-200 ppm of nutrients. The plants are fertilized every watering until they are ready for sale. Plants should also be hardened before they are sold. SALVIA (Salvia splendens) There are five groups of Salvias that range in height from 8-10 inches to 26-30 in. Popular red cultivars are ‘St. John’s Fire’ and ‘Red Pillar’. The cultivars of the taller classes of Salvia are ‘Blaze of Fire,’ ‘Evening Glow,’ and ‘Bonfire.’ These species of Salvia farinaceae provides purple, blue, and white Salvia. The best percentage germination occurs in a medium with low salt content. The medium must not be fumigated with methyl bromide as this chemical is toxic to Salvia. The seeds are sown on the surface of the medium, then the flats are covered with a white opaque plastic sheet or placed under mist to maintain a high relative humidity. The plants require full light intensity. Because of their sensitivity to high soluble salts, they should be fertilized with a solution with a maximum concentration of about 150 ppm N. ZINNIA (Zinnia elegans) Zinnias are native to Mexico, and prefer summer conditions. They range in size from the tiny 6 – inches tall ‘Thumbelina,’ to the giant cactus-flowered ‘State Fair Mix’, which grow to about 30-36 inches. Zinnias grow very quickly from seed. They should not be allowed to grow too tall, however, before they are sold because too much growth results is weak floppy stems. An exception is the dwarf cultivar ‘Thumbelina,’ which must be allowed to grow longer to produce blooms.  96 Zinnias require warm temperatures. The seeds germinate at 21ºC. After seedling emergence, they must be moved to a cooler place of about 15.5ºC, which is the lowest temperature to which the plants can be exposed. At lower temperature, they suffer from thermal shock with the consequence of stunted growth. Different from the Zinnia elegans types are the graceful Zinnia angustifolia. These graceful, 14 – inches Zinnia plants produce single star-shaped flowers up to 2 inches across. Cultivars in this group include ‘Star Orange’ and ‘Star Mix.’ The Stars tolerate heat, humidity, and drought for exceptional landscape use, and are sufficiently vigorous to fill a bed quickly. Plants have a looser, more informal look. Application Let’s connect the dots! After learning the essentials of this lesson, let us try to apply practical situations relevant to this topic. Your task is to identify 3 bedding plants present in your area. Then take a selfie photo of each plants you identified and post it in our UVE (NOTE: ONLY 3 PHOTOS per student). Follow safety protocols when done outside your home. Upon posting, each photo will be labelled with a narration on how those crops are produced. 3-5 sentences only. Your output must be in a Microsoft word or PDF. Closure Congratulations! You've just hurdled again this lesson with ease. Now move forward to the next lesson!