Chrysanthemum

Propagation of Year Round Pot

www.yoder-toddington.co.uk Yoder Toddington, Toddington Lane, Littlehampton, West Sussex BN17 7PL Yoder Toddington 2003

Propagation of Year Round Pot Chrysanthemum Cuttings

Page

1. 2. 3. 4. 5. 6.

The Objective The Compost The Cuttings The Environment Chemical Treatments Summary

3 3 4 5 6 7

www.yoder-toddington.co.uk Yoder Toddington, Toddington Lane, Littlehampton, West Sussex BN17 7PL Yoder Toddington 2003

1.

THE OBJECTIVE Fast uniform rooting leading to even plant establishment both within and between the pots and with plants that are free from any pests and disease. Maintaining plant turgidity at all stages of the process is a key factor.

2.

THE COMPOST The growing media is also the rooting media so the structure and the nutritional components of the compost have to be decided with propagation of the cuttings in mind. Chrysanthemums will root in composts with a wide range of nutrient levels but in recent years many growers have seen the advantage of using a compost with a lower nutrient balance, e.g. with only 100-120 ppm N. Experience has shown that rooting is marginally faster at these levels. To encourage fast and even rooting a compost with an open structure should be used with a high percentage of course grade peat (40% in winter) or perlite. Oxygen in the compost is vital for root growth so the structure of the compost must allow aeration even after watering. For optimum rooting consider the following:

Minimize the handling of the compost. The more the compost is turned or mixed the greater the risk of affecting the structure. Avoid mixing any additives unless absolutely necessary. If additives are required (e.g. Aaterra) then it is best if the compost manufacturer mixes them. Store the compost in a dry and if possible relatively warm place. Time deliveries of compost so that you reduce storage to a maximum of 4-6 weeks. The pots must be evenly filled with compost to just above the rim of the pot. If the compost is cold, try to fill pots, transfer to the house, water 24 hours prior to sticking so that the compost has time to warm up. Moisten the compost 24 hours prior to sticking. The ideal method is to use mist lines, alternatively use a hose and rose (not too coarse). The compost does not have to be saturated at this stage but it should be evenly moist from the surface to the base. Avoid the use of very cold water particularly in the winter. Avoid pot filling and leaving the compost dry for too long. The longer the compost stands dry the more difficult it is to re-wet.

www.yoder-toddington.co.uk Yoder Toddington, Toddington Lane, Littlehampton, West Sussex BN17 7PL Yoder Toddington 2003

Although not recommended some growers do stick into dry compost. This can work well but watering in after sticking is easier with less water required when the pots are moist pre sticking. We believe that sticking into a moistened compost leads to less errors when watering in after sticking, i.e. less chance of having the compost too wet or too dry or too cold.

3.

THE CUTTINGS For optimum rooting consider the following: Try to stick the cuttings as soon after receipt as possible, i.e. reduce the period in cold storage to a minimum. In summer ensure that cuttings have cooled following any heat build up during transit. Stagger removal from the cold store. Never have boxes of cuttings standing in the house for too long prior to sticking. Inspect the cuttings for signs of any pests, leaf/tip rotting and torn bases and discard any dubious material. Sticking must be uniform, with 5 cuttings equidistant around the pot. Stick to a depth of 1.5 to 2 cms and no more than 1 cm away from the edge of the pot. Sticking too deeply can lead to a higher risk of stem and/or leaf rotting. Uneven depth of sticking can lead to uneven rooting and growth. Watering must be done evenly as soon after sticking as possible, ensuring that the compost is thoroughly wet from the top to the base of the pot. If a pot is removed after watering in the entire surface of the compost should "glisten" when viewed. Use this as a guide as to whether enough water has been given. If insufficient water is given there will not be enough humidity under the sheets to keep the cuttings turgid. If watered in by hand ensure the pressure of the water is not too high as this will disturb the cuttings and may effect the structure of the compost. Cover the cuttings with polythene as soon after sticking as possible and ensure that the cuttings are well sealed. In hot weather water and cover each container as it is completed. Never allow cuttings to wilt. Ensure that the cuttings are moved to half/final space 12-14 days after sticking. To long at nurse space can cause the cuttings to stretch. Spacing too early must also be avoided as the cuttings need to be weaned and turgid prior to spacing. For the best uniformity use a nurse spacing of 15/16cms x 15/16 cms (44-39 pots m) rather than true pot thick 14cms x 14cms (51pots m)

www.yoder-toddington.co.uk Yoder Toddington, Toddington Lane, Littlehampton, West Sussex BN17 7PL Yoder Toddington 2003

 Follow good practices to ensure that cuttings gain turgidity as soon as possible. A cutting that is allowed to wilt will be slower to root and will not maximum its potential. In the extreme the cuttings will fail to root and this will cause extra work on "making up" pots after propagation.

4.

THE ENVIRONMENT For optimum rooting consider the following: Temperatures The compost temperatures must be maintained at 20-22C, with air temperature at 17C. If the compost temperatures are outside these parameters then slow rooting and in the extreme, failure to root will occur. Avoid high air temperatures. If the air temperature (even at night) is excessive then the cuttings can "cook" under the polythene sheets and serious losses can occur. If the air temperature of the propagation unit is too low, then cooling can occur under the sheet which can result in slow rooting. Shading For the months of October to March use clear polythene. For April to September use milky polythene. Additional shading will be required on hot sunny days, particularly for the May to August period. High natural radiation will cause heat build up under the polythene and scorching of cuttings. If internal, automatic shading is not available then external shading paints will be required. In extreme conditions during the summer a double layer of milky polythene or the use of a layer of moist agryl (must always be moist) on top of the polythene can be considered to keep the cuttings cool. Humidity The cuttings will only root if the humidity under the sheets is optimised. Ensure that you can see "beads" of moisture on the underside of the polythene at all times. If the polythene clears of moisture then uncover, inspect the cuttings and re-water as required. The polythene sheets can be removed once the roots are 1-2 cms in length (after 8-10 days) and the cuttings are turgid. Some varieties, e.g. Fine Time may require sheeting down for longer. The correct timing of sheet removal is vital if cuttings are to remain turgid. However the cuttings will still require high humidity levels and need to be "weaned" otherwise plant stress will occur. Ideally this is done with mist lines where frequent short bursts of moisture are given for the first two to three days after sheet removal. This can be reduced as the plants are able to transpire and remain turgid without additional moisture. It is important to note that too much water during the weaning process can leach nutrients from both the leaves and the compost. Also if the compost becomes too wet then rooting and growth will be

www.yoder-toddington.co.uk Yoder Toddington, Toddington Lane, Littlehampton, West Sussex BN17 7PL Yoder Toddington 2003

inhibited. These factors are the reason that propagation under polythene sheets is favoured over mist propagation. If mist lines are not available then a lot of attention to detail will be required once the cuttings have been uncovered to ensure that they do not wilt. Do not "damp down" with a coarse jet of water as this will disturb the cuttings and make the compost too wet. For a grower without mist lines a lance, attached to a hose, with mist nozzles fitted should be used rather than a hose and rose which can make the compost wet. Keeping the cuttings turgid is the key. Until the plants are able to sustain themselves then the leaf surfaces must have a continuous film of moisture. Cuttings will actually root "in the air" which emphasizes the importance of the humidity levels (and good compost aeration). Long Day Treatments Give a minimum of 12 days in summer and 16 days in winter. Additional long days will enhance quality, i.e. 16 days in summer and 18-21 in winter. The intensity of illumination should be between 100-120 lux. This can be provided by using 150 watt tungsten filament lamps 2.4m x 2.4m at a height from the crop of 2.0m. The normal lighting periods during the night are: November to February 5 hours March to May 4 hours * June and July 3 hours * August to October 4 hours * * If the propagation area is covered at night with a blackout screen than light for 5 hours throughout the year.

5.

CHEMICAL TREATMENTS (i) B9 Treatments Application rates will depend on variety and the time of year but the sooner the treatment is carried out the better. Treatment as soon as the cuttings are nd turgid is best, say 48 hours after sticking with an optional 2 application 810 days later. Treatment is best done during the late afternoon with the cuttings being re-covered with polythene immediately so that humidity levels are maintained. If treatment cannot be done 48 hours after sticking then treat as soon as the polythene sheets are removed. The later the treatment the less effective it will be. Treatment during the winter will generally be more dilute to help give improved stem strength.

www.yoder-toddington.co.uk Yoder Toddington, Toddington Lane, Littlehampton, West Sussex BN17 7PL Yoder Toddington 2003

Rates in the summer will be higher to control overall height and reduce stretch. (ii) Fungicide Can be used at watering in or at any time during the propagation period. Chemicals used include Rovral or Daconil. (iii) Insecticides Not commonly used during propagation but the use of Dynamec just prior to spacing out will give early protection/control of thrips, leaf miners and red spider mite.

6.

SUMMARY The propagation of cuttings must receive the highest possible priority. Correct management inputs and attention to detail is vital. Failure to achieve good results in the propagation area will have an adverse affected on the uniformity and quality of the crop. Maintaining plant turgidity at all stages of the process is a key factor.

www.yoder-toddington.co.uk Yoder Toddington, Toddington Lane, Littlehampton, West Sussex BN17 7PL Yoder Toddington 2003