Carnation Cultivation Under Greenhouse

Protected cultivation of carnation flowers is getting popular in India as demand for carnation flowers is increasing notably. Carnation cultivation is a profitable agribusiness but demands high initial investment.

Also referred to as ‘Clove Gilly Flowers’, Carnation is one of the much-admired cut flowers across the world. With its botanical name as Dianthus caryophyllus L. carnation belongs to the floral family of Caryophyllaceae. Chiefly grown in the winter season, the cut flower is extensively used to decorate beds, flower pots and has emerged as the first choice for ornamenting events like wedding, anniversary, birthday, and celebration parties and so on. Due to its high demand in the market, it’s cultivated on large scale commercially primarily under greenhouse settings in the United States, Europe as well in India. While it has three major varieties and grows in a range of colours, for potential cultivators, it is essential to select the variety to be grown taking into consideration the adaptability of the species to that particular tropical condition, disease/ control measures, rather than merely on colour and care concern.

Carnation Varieties

As stated above carnation grows in varieties and its grouping has been made in terms of the volume of the flowers, characteristic, and typical uses.

Greenhouse Structure for Cultivation of Carnation

Cultivation of Carnation has been popular in protected greenhouse settings which is ideally the best method to meet the demands of plants, provide them protection and maintenance as desired and fetch best quality and yield. Construction of the greenhouse must be as simple as possible while cultivators should follow due diligence to meet the basic requirements that carnation needs in a greenhouse.

• The green house must not be too low to avoid high humidity, lack of aeration and increased heat which is not fit for growing carnation;
• Providing them with a specious area keeping sufficient airspace in per square metre with mesh in your plastic greenhouse should be the best choice
• Instead of constructing a huge greenhouse consider parting them in sections with smaller space that helps have better control over indoor climate and ventilation.
• Use low density LDPE type polyethylene with 200 micron (max.) thickness. And consider replacing the materials once in 3 years.
• Ideal temperature needed in the greenhouse is – for the day time is 22 – 25 degree C while during the night it should be 10°C and 12°C.  
• Relative humidity: 50-60% 
• CO-2 500-1500 PPM

Propagation of Carnation: 

Even though carnation can be propagated by seeds, layering, and cutting methods, the most preferred means are sowing of seeds and cutting of stems. 

By seeds 

Propagation through sowing of seeds is ideal for new cultivators. Seeding needs to be done during Sept-Oct month on raised bed and should be watered on a daily basis. It takes nearly seven days for seeds to germinate. Seedlings should be transplanted keeping a distance of 20 x 30 or 30 x 45 cm in the greenhouse bed. Keep a seed rate @ 400 to 500 grams / ha. 

Terminal cutting  

Propagation of carnation through terminal cutting observes the highest success rate, if the procedure is property followed. Remember, cutting of the terminal should be 8-10 in length and use a sharp knife for cutting just below the node. Discard 2 or 3 leaves from the lower most part. Keep the cutting dipped into a combined solution of Dithane M. 45 (0.1%) and Bavistin (0.1%) for 5-7 min. Again, dip the lower end of the cutting in NAA 500 PPM solution for another 5 seconds. Make sure before you plant the terminal into the greenhouse, the land is prepared and well sterilised as stated below. Rooting occurs within 3-4 weeks.

Land preparation

Soil should ideally be loamy and red in nature containing adequate amounts of organic matter for desired growth of carnation. The branching fibrous root system of carnation needs the presence of SOM (soil organic matter) and microorganism action in the soil that foster growth of a robust root system. This not only helps plants to absorb micronutrients, water, and minerals from soil but reduces soil erosion. Make sure soil contains a maximum 6.5 pH level while addition of calcium carbonate/ dolomite limestone helps in fixing the acidic condition and also supplies magnesium and calcium for nutrition of the plant. Consider deep and thorough ploughing of the land before preparation of bed and sowing. 

Land fumigation 

Having soil sterilization before preparation of the bed is a vital need. Consider mixing Formaldehyde with water @ 1:10 ratio and use the solution to wet the beds and keep them wrapped with plastic for 5-7 days to lessen evaporation and absorb needed chemicals. For effective fumigation of soil beds, use of granular soil fumigants like Dazomet or Basamid @ 30 grams per sq. mt is the best alternative to rid it of insects, weeds, and microbes that cause root decay. 

Bed preparation 

• Always go for a raised bed preferably having 30 cm height and 90 to 100 cm width. Beds should be inclined (minimally) toward the gutter of the greenhouse that helps proper draining. 
• Keep space of 50 cm as path for among beds for working handiness or providing nourishment to plant life. 
• Depending on the clay contains, consider adding sandy soil, farmyard compost, and rotten saw dust or coir pith in a proportion of 4: 2: 1 while preparing the beds. 
• Sowing should be made with needed spacing as recommended 

Spacing and planting

Planting needs to be carried out with spacing that generally differs according to the branching pattern of the species of Carnation. Therefore, before sowing, study the plant habit and accordingly consider spacing of 15 x 18 cm, 15 x 10 cm, 15 x 15 cm, and 15 x 20 cm while 30- 45 plants can be housed in every square metre of the bed. If you don’t have any information about the flora, it would be the best choice to have 15x20cm spacing. After cropping, they should be kept protected under shade for the first few days.  

Bed netting and staking 

Bed netting and staking is a vital part for cropping carnations because, with thin stems they’ve a propensity to bend sideways if not offered proper support. The bed should be prepared with 4 layers of netting/staking starting from the bed level with a measurement having (1st layer 7.5 x 7.5 cm/ 2nd layer 10 x 10 cm/ 3rd layer 12.5 x 12.5 cm and 4th layer 15x 15 cm) to provide maximum support. Consider integrated use of metallic wire and nylon mesh along with bamboo poles maintaining 2 metre distance among them.

Pinching

Pinching is a great method that encourages growth of more quality flowering with increased side shoots. The procedure involves pinching of growing main shoot and subsequently the lateral shoots through single, one-and-half or double pinching methods. It takes nearly 3-4 weeks for the plant to acquire six nodes when you should perform the first pinching. This will give birth to six lateral shoots. After a week, in the next session of ‘one and half pinch’, 2-3 of the newly grown shoots should be pinched. In case of ‘double pinch’, all lateral shoots need to be pinched off. Choose morning time for pinching. 

Disbudding

Disbudding involves elimination of unwanted buds from time to time that helps the retained ones fetch maximum nutrients essential for their faster and steady nurturing. Depending on the type of carnation, you have to choose which buds need to be removed. Disbudding should be done with a sharp knife carefully and plants should not be jerked.   

Fertiliser management

Effective fertilising is a cruel need to save plants from calcium and boron deficiency that leads to mortality. Introduce Phosphorus @400 g, Magnesium sulphate 0.5 kg per 100 sq ft respectively as balsa; requirement. Neem cake @2.5 ton/ hectare should be included too.     

Now, depending on the phase of the plant and soil needs continue nutrient management as under to maximise production.

Irrigation 

Use new generation overhead sprinklers to supply watering evenly throughout the zone for the first 21 days that helps stop budding plants from dying. Later drip irrigation systems should be followed.  

Disease management

Red spider mites-Tetranychus urticae

Symptoms-Hardly noticeable red spider mites suck the juice found in the leaves, which can be spotted with the yellow and white tiny specks on them. They can result in destructive plague fast making the foliage to drip prematurely and plants to die. 

Management-Immediately eliminate the leaf remains and apply Abamectin or Vermitec(1.9 EC)@ 0.5ml per litre or Azardiractin spray 50,000ppm @3-4 ml/litre of water and spray. 

Bud borer (Helicoverpa armigera)

Symptoms-The caterpillar species infest leaves and buds which can be noticed from boring holes on lively flower buds causing them to fall off. 

Management-Apply Bacillus Thuringiensis spray @ 2gm/litre. Arrange pheromone sex traps around 4 to 6 numbers per acre of land and release 1- 1.5 lacks of Trichogramma egg parasitoid/ acre for fast result. 

Vascular wilt (F.oxysporum f.sp. dianthi)

Symptom-Infected plants develop a dull green colour running to straw like and eventually wilt. The problem may be found in one or more sections of the plant. 

Bacterial wilt (Pseudomonas caryophylli)

Symptoms- An extremely harming bacterial infection causes wilting of shoots while splitting the stems and stripping the vascular system. Leaves turn into greenish grey and then yellow before drying completely. Rotting roots and developing cracks in the tissues within nodes is found widespread. 

Management- Drenching the soil with Difenoconazole @ 0.05 % or Carbendazim @ 0.1 % @ 25g per square metre and foliar with Bacillus amyloliquefaciens @ 0.5 % results great. Both should be applied once in a month.

Leaf scarring (Alternaria dianthi)

Symptoms- Leaves border emerge tan to brown marks with purple borders causing faster destroy of leaves and spoil growth of plant

Management- Pick and discard the leaves as soon they come out. The plague can be effectively controlled by applying Chlorothalonil 0.2%, Captafol 0.2%, or Iprodion 0.2%.

Flower decay (Botrytis cinerea)

Symptoms – Flowers appear like papery brown covered with hairy grey masses of deadly Mycelium fungus while leaves often develop brown streaks on them. Mainly occurs during wet and humid weather conditions.  

Management – Removal of exhausted flowers is the first step. Have an eye to sanitation procedures and stay away from wetting flowers during watering. Use of fungicide sprays is proven effective. 

Root rotting 

Symptoms-Be wary of rotting at the soil level stem that eventually infects the plant in all terms. If roots are affected that leads to fading of leaves right from the lowest part to upwards and causes drying along with flowers. 

Management-Moisture regulation should be the first aim to control infection. Equally, use of fungicides like Benomyl 0.2% or Iprodion composition 0.2% or combination of Metalaxyl + Mancozeb 0.2% or Fosetyl-Al 0.2% can produce great results depending on the type of infection. 

Nematodes

Symptoms-Nematode is harming worms that cause root knots on the feeder roots while stopping the roots ability to uptake water and nutrition. Foliage exhibits nutrition deficiency and flower size is reduced.

Management- Apply FYM containing bio-agents like Pochonia chlamydosporia plus Paecilomyces lilacinus before plantation. Also, use Carbofuran 3 gram to 5 gm per square metre of soil bed and repeat the same after 45 days.

Harvest/ Post Harvest/Yield 

Carnation takes nearly 110-120 days to come out with maximum flowering. After harvesting, it’s essential to rinse the flowers with trimmed stems in a bucket containing needed biocide and acidic solution (Ph 4.5) for a few minutes, vital for preservation. Store them in 20 degree C temperature for 3-4 hours and then take out for grading and bunching. Choose uniformly bloomed healthy flowers based on the bud size and stem length and prepare a bunch of 10, 15, 20, or 25 flowers which should be tied well and wrapped with butter paper sleeves. Now it’s ready for packing and distribution. A commercially developed greenhouse is capable of producing 200-250 of standard type and 250-300 of spray carnation/ square feet 200 every year.