Chrysanthemums
The genus chrysanthemum compositae consists of more than 200 species of hardy annuals and herbaceous and greenhouse perennials.
For ease of reference, the following data has been divided into the more commonly grown annual, perennial and florist species
Annual Chrysanthemums; are among the best 'cut flowers' for floral arrangements.
They like full sun and well-drained soil, and like other chrysanthemums; they prefer cool weather.
Ensure the soil is kept adequately moist.
Cultivation;
Week 14; Sow seed in pots / trays of seed compost and germinate at 14°-20°C (57°-68°F)
Seeds should take around five to seven days to germinate.
Week 16; If large enough to handle, prick out seedlings into 75mm (3") pots or cell trays of potting compost.
Grow them on in good light (but not direct sunlight) for a couple of weeks at the same temperature, then place them in a frost free cold frame until planting out time.
Week 21; Plant out in final quarters 200-300mm (8"-12") apart in groups for effect.
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Perennial & Florist chrysanthemums
Most of these varieties result from hybridizing many species, most of which originated in the Far East.
These hybridizations have resulted in many types of flower heads, petal formations, and flowering times.
To give some sort of order to these various forms; many societies across the world have grouped the different types together in relation to the growing season in their respective countries.
The following classifications are those laid down by the National Chrysanthemum society in the UK;
Section 1; Large exhibition Section 16; Large October flowering Section 2; Medium Exhibition Section 17; Singles Section 3; Exhibition incurved* Section 18; Pompons Section 4; Reflexed decorative* Section 19; Sprays. Section 5; Intermediate decorative* Section 6; Anemone* Section 7; Singles* Section 8; Pompons Section 23; Incurved decorative° Section 9; Sprays Section 24; Reflexed decorative° Section 10; Spidery, Plumed, Feathery Section 25; Intermediate decorative° Section 11; any other types Section 26; Anemone. Section 27; Singles° Section 13; Incurved decorative * Section 28; Pompons° Section 14; Reflexed decorative* Section 29; Sprays Section 15; Intermediate decorative* Section 30; All other types.
Classifications;
Sections 1-11 inclusive are late flowering varieties.
Those marked thus * are further classified as; a=large flowered, b=medium flowered.
Section 9 is futher classified as; a=anemone, b=pompon, c=reflex d=single
Sections 13-19 are October flowering varieties.
Those marked thus * are further classified as; a=large, b=medium
Note; this section / group has been produced to cater for types that flower too early to be considered as a ‘late flowering’ variety, but too late to be considered as an ‘early flowering’ variety.
For exhibition purposes these types can be entered in either Early or Late flowering shows!
Sections 23-30 inclusive are early flowering varieties;
Definition; An early flowering variety; is a variety that blooms in the open ground before October 1 st without any protection whatsoever.
Note; this definition does not debar exhibitors from protecting blooms from weather damage (see rule 3 of the ‘Judging manual)
Those marked thus ° are further classified as; a=large flowered, b=medium flowered.
Section 29 is futher classified as; a=anemone, b=pompon, c=reflex d=single
Colours;
For exhibition purposes ‘colours’ have been classified as follows;
The colour classification does not have to be the precise colour of the variety.
It is merely a general classification to assist exhibitors and judges to decide whether a particular variety is, or is not, eligible to be shown in a particular class.
For example, varieties that are cream in colour are classified as pale yellow; orange varieties are classified as yellow; and crimson varieties are classified as red.
Key to colour classification;
B Bronze Pu Purple Y Yellow LB Light Bronze R Red PY Pale Yellow P Pink S Salmon O Other colours PP Pale Pink W White
Note to would be buyers;
It is best to purchase plants at flowering time, or to choose them from an illustrated catalogue.
Flower types;
- Early-flowering chrysanthemums; bloom from late summer to early autumn, and are grown outdoors.
- Late-flowering chrysanthemums; are grown in pots outdoors in summer and brought into a greenhouse, where they flower from autumn until late winter.
- Early charms; flower from late summer to mid-autumn and are grown outdoors either in containers or in borders.
Cultivation; is similar for early and late-flowering types, but plants for exhibition need more time and attention; e.g. disbudding!
A disbud chrysanthemum; is formed by removing the lateral buds at an early stage to leave a single, terminal bud that will then produce a much larger flower head.
Disbuds
Incurved;
Fully double flower heads with incurved petals closing tightly over the crown.
Reflexed;
Fully double flower heads with curved petals reflexing back to touch the stem.
Intermediate;
Fully double flower heads with loosely incurving petals and a regular shape.
Single;
Flower heads have a prominent central disc, and 5 rows of flat-petalled florets.
Spider;
Fully double flower heads with long fine pendent florets with hooked or coiled tips
Various varieties
Sprays;
A type of Chrysanthemums that naturally forms a number of flower heads on the same stem.
Single ;
Flower heads have a prominent central disc, and flat-petalled florets.
Reflexed single;
Fully double flower heads with partly reflexed petals and a spiky outline.
Anemone;
Single flower heads each with a dome-shaped disc, and flat, or occasionally spoon-shaped, petals.
Charm;
Sometimes known as garden 'mums or cushion 'mums, these dwarf chrysanthemums
Various varieties
Annual programme;Table of cultural tasks for a growing season;
Task
Charms
Sprays
Earlies
Lates
Week N° Week N° Week N° Week N° Put stools on hot bed 2-4 2-4 1-4 1-4 Take cuttings 8-10 8-10 5-8 5-8 Pot up rooted cuttings 12-14 10-12 8-12 8-12 Place cuttings in coldframe 14-15 12-15 12-14 12-14 Stopping programme 20-22 20-22 14-18 18-24 Prepare beds and or pots* 20-22 18-20 18-20 18-20* Plant out 20-22 20-22 20-22 24-26 Nitrogen feed 24-26 24-26 24-26 28-32 Secure bud / Disbud 26-30 26-30 26-30 28-32 Fix bud bags (if required) - - 26-30 28-32 Potash feed 28-30 28-30 28-30 32-34 Flowering 30> 30> 30> 42> Lift and store stools 44-46 44-46 44-46 48-50
Cultivation of purchased stock - all types;
Unpack plants immediately on receipt.
If plants are received before it is safe to plant them out where they are to flower, pot them up as soon as possible into 90mm (3½”) pots using a soil-less potting compost e.g. John Innes No2.
If you can not deal with them immediately, place the plants upright in a box / tray and gently spray them with water, then place them in a well lit spot the, but not in direct sunlight.
Keep the compost open textured – DO NOT over compress.
Water them in, then don’t water again for several days, i.e. until the compost has started to dry out.
Grow on in a cool greenhouse, cold frame, conservatory or airy porch in full light but avoid direct sunlight.
Do not be tempted to plant out until all danger of late frost has passed.
Note; Sometimes plants sent my ‘mail order’ can be somewhat drawn and leggy.
There is not much a grower can do about this, however! If this plant is potted on for a few days until it establishes itself, the growing tip can be removed.
This tip can then be treated as a 'new cutting' and should perform as well as a cutting taken from your own stock (see below) plus you have created the potential to double your stock.
Cultivation of own saved stock- all types;
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
Prepare cutting material from Week 1 onwards; (see table above)
Water previously boxed stools then place them on a hot bed (slide 4) set to maintain a soil temperature of around 15°C (60°F)
Maintain a minimum air temperature of 4°C (40°F)
Prepare 'cuttings' compost (Slides 1-3) by seiving multi-purpose compost to remove any large lumps, then combine this with sharp or silver sand at a ratio of around 2-1 (or to a ratio of your own choosing)
Prepare a tray by filling it with the pre-prepared compost, and lightly compact it by tapping it gently on the bench then soak it thoroughly with water.
Sprinkle about 3mm (1/8") of dry silver sand over the compost.
Select cuttings approx 2” (50mm) long radiating from soil level i.e. basal cuttings.(slides 5-6)
Remove lower leaves to expose approx 1” (25mm) of stem. (slide 7)
An Irishman's cutting i.e. one that is already rooted. (slide 8)
Dip cutting in rooting powder /fluid (slide 9)
Insert the cutting into the compost and label variety (slide 10)
Normally one can get around 40 cuttings in a standard 350 x 200mm (14" x 8") tray (slide 11- 12)
Place the tray in a warm place, preferably with bottom heat.
A soil temperature of around 15°C (60°F) and a minimum air temperature of 4°C (40°F) are ideal.
Ensure that the cuttings get plenty of light, but not direct sunlight.
Spray them at least once per day with either fresh water or a fungicide mixture to prevent dehydration and damping off.
Normally cuttings take 12 to 15 days to root.
A good sign that they have rooted is, the growing tip will be a ‘fresh’ green colour.
Pot rooted cuttings up into 75 mm (3") pots of potting compost.(slide 13)
Harden off;
Approx 10-14 days before you intend to set the plants out, start hardening them off by increasing the ventilation in the greenhouse, and/or placing the plants in a cold frame.
Alternatively; move them outside during the day and fetch them back inside overnight.
Soil preparation;
Chrysanthemums require a fairly sunny sheltered site.
A well-drained, slightly acid soil that has a pH value of 6.5 is ideal.
For most soils, the ground should be prepared in late autumn or early winter, incorporating plenty of well-rotted organic matter.
Plant out:
Early flowering varieties; when all fear of late frost has passed, remove the plants from their pots and plant out in pre-prepared beds and borders.(slide 14 - 17)
Set them 400-500mm (15”-18”) apart supporting each with a 1200mm (4’) cane/stake.
To avoid any damage to the roots, position the supports in the hole prior to planting.
Tie the plant loosely to the support at regular intervals as the plant grows taller.
An alternative method; of support is to use 100mm (4") square mesh supported horizontally from posts/stakes, and letting the plants grow through it.
Optional; Use of a weed suppressant sheet can minimise the need to hand weed or hoe between plants, which is particularly helpful when the plants are fully grown.
Another alternative is to place the plants in planters or containers, (singly or in groups subject to the size of the container).
Growing in Containers;
Late flowering varieties; should be potted up every 5-6 weeks from initial 'potting up' until they are in their final 250mm diameter pots.
Stake the plants as you would with early flowering varieties.
Stand the pots outdoors throughout the summer, in a sunny, sheltered position.
Note; Pot grown plants have a tendency to be blown over.
To cater for this; form a framework with a horizontal wire between two fixed points and tie the stakes into the horizontal wire.
Using a ‘loam based’ compost rather than a ‘soilless’ one will make for a heavier base thus increasing stability.
Water plants when necessary; never allow the compost to dry out completely.
Charm varieties; can be planted directly into garden beds / borders or in pots / tubs on the patio.
Their cultivation requirements are similar to early-flowering chrysanthemums when grown outside, and to late-flowering ones when grown in containers,
except that charms should not be disbudded.
As with early flowering varieties; plant or place outdoors when all fear of frost has passed.
Set plants in beds / borders 300-400mm (12”-15”) apart, or insert three plants in a 300mm (12in) pot.
Charms are self-supporting, so do not need to be staked.
Watering; (all types)
Water in after planting, but not again for at least three or four days.
Water regularly from this time onwards, giving the plants a thorough soaking every seven days in all but the rainiest of weather.
Feeding; ( see table )
Feed with a liquid fertiliser every 7- 10 days from mid June until the buds start to show colour.
Stop feeding as the buds show colour, to prevent the blooms becoming too soft and prone to damage.
Stopping;
This consists of pinching out the growing tips to encourage flower-bearing laterals.
Note; See table above; or refer to a growers' catalogue or specialist / society publication for precise timing.
- Charms; This is best carried out three or four times a season to encourage bushiness.
When the plants have grown to about 100-150mm (4"-6") high pinch out the top 13mm (1/2”) of the main shoot.
Repeat this task every three to four weeks thereafter to promote 'bushiness' and ultimately more flowers.
Every three to four weeks thereafter do the same again.
Note; ensure that you stop every shoot, otherwise your plant will be out of balance at flowering time.
- Disbuds; ‘Stopping’ is best carried out over a three or four week period and completed by Week 22.
When the plants have grown to about 200-250mm (8”-10”) high pinch out the top 50mm (2”) of the main shoot (growing tip) to encourage more side shoots.
If you are growing for exhibition purposes, then you would limit the number of side shoots to 2-4 stems per plant depending upon variety.
When the buds/s appear remove all the buds on each stem apart from the centre bud (crown bud)
This is known as ‘securing the bud’, hence the name 'disbuds'
- Sprays; The method of stopping this type is the same as for ‘disbuds’ but securing the bud’ is somewhat different!
In fact it is quite the reverse!
That is; you only remove the centre (crown) bud and leave the other buds to develop as a spray of flowers.
Tips;
A useful tip to keep in mind for future propagation (with all varieties) is; mark blooms of exceptional quality so that they can be used for propagating new plants the following year.
Similarly check that your label details are correct when plants come into flower.
Late flowering varieties;
Circa Week 38; Keep a watchful eye on late flowering varieties and move those showing colour into the greenhouse as soon as possible.
As a general rule, growers in the north would be wise to move all their pots under cover at this time, southern grower should do this by the end of the month.
You can reduce the risk of bud damage when maneuvering large plants into their flowering quarters by placing the pots in a bucket and walking backwards through the greenhouse door.
Initially maintain a temperature of around 10°C (50°F).
The greenhouse should be shaded, if necessary, to keep the temperature low.
To encourage good air circulation around the plant/s, remove all the leaves on the main stem up to the break point.
Condensation can often be a problem at this time of year.
To alleviate this problem suspend a layer of agro-fleece between the top of the plants and the glass to absorb any excess moisture.
It is wise to spray all plants thoroughly with a combined insecticide / fungicide before moving them under cover.
Laying the pots at an angle will help make spraying easier.
Continue to feed with a balanced liquid fertilizer until the flower colour just begins to show.
Increase the temperature when they begin to flower.
Growing blooms for exhibition; (early & late varieties)
Blooms grown outdoors for exhibition require protection from the elements.
This can be done in a number of ways, for example;
If grown in large numbers; a structure similar to a ‘car port’ can be erected.
This is a structure with a transparent roof and no sides; although in exposed areas it is advisable to erect a fine mesh net windbreak around the exposed edges.
Further protection can be offered by fixing greaseproof bags to each bloom, particularly the lighter coloured varieties e.g. white or yellow.
The bags are fitted just as the calyx has broken and colour is showing.
Initially the bud is enclosed in a smallish bag, of say 150 x 150mm (6” x 6”) in size and fastened with a twist-tie.
This bag is left on for 7-10 days.
When the bud reaches what is known as the "paintbrush / shuttlecock” stage; the small bag is removed and replaced with a larger 300 x 330mm (12” x 13”) bag.
Prior to fitting the bags spray or dust the buds to remove any pests before covering them.
Smearing the stem below the bud with petroleum jelly will also assist in keeping pests such as earwigs & caterpillars off the buds.
Note; developed blooms are quite heavy, and care must be taken to support the stems so that the heads do not snap off in high winds.
Late flowering varieties flowering time can be manipulated by regulating the periods of light and darkness they receive.
Bud-forming normally requires around 10 hours of continuous darkness. This can be advanced or retarded with the use of artificial light or the introduction of shading.
That is; shading the plant for an extra two or three hours per day (say up to 14 hours per day) will hasten bud formation, conversely increasing the available light will delay the bud formation.
This can be done mechanically by fitting a timer to a light above the plants set for example; to come on two hours before dawn and two hours after sunset.
Note; it may take up to three weeks for this practice to work.
Preparing for exhibition;
Study the ‘show schedule' and decide which classes you intend to enter.
Cut the selected blooms for your entry when they are fully open, and immediately plunge the stems into a tub of deep water for 24 hours.
Keep them quite cool!
Too high temperatures can result in the petals ‘damping off’
Displaying the blooms correctly is as equally important as growing the perfect bloom.
Many a competition has been lost due to poor ‘staging’
Check the schedule and ensure that you have the correct number of blooms in each vase, this is usually one bloom, three blooms or five or a combination of these in multi-vase classes.
Stage a single bloom in the centre of the vase.
Ensure that it is secure and vertical by packing the vase with newspaper.
Some of the more dedicated exhibitors might use florists foam (oasis) in lieu of paper.
A vase of three blooms can be staged in two ways subject to the size of the blooms you have available.
The most common practice is to stage two blooms at the back of the exhibit and insert the third bloom in front of these, placing it slightly lower so as not to screen the back two blooms.
In the event that say you have two blooms that are slightly smaller than the third, it is sometimes better to create an optical illusion by putting the single larger bloom at the back, and the two smaller blooms at the front of the exhibit.
This can create the illusion that the large bloom being further away looks slightly smaller, and the two smaller blooms being nearer look larger, so in this way they all appear to be of a similar size.
A vase of five blooms is staged in a similar manner but with three at the back and two in the front.
Note; The alternative staging described for a three vase for dis-similar sized blooms, can also apply with a five flowered vase, in this case two at back three at front!
In a multi-vase class a better arrangement can often be had by sitting the vases on blocks of wood or boxes to give a tiered effect.
Lifting/Storing:
Early-flowering chrysanthemums may be overwintered in the ground in mild climates that are frost-free, and their stems cut down in spring.
In temperate climates, however, plants are best lifted and stored.
That is; after flowering, plants should be cut down to 100-150mm (4"-6") above soil level, lifted, and placed in boxes or trays of potting compost.
It is advantageous to remove all basal growth from around the base of the plant to induce a dormant period and reduce the risk of botrytis.
Ensure that the compost is slightly moist and that the stools are not buried too deeply.
Do not water them in: keep them almost dry to minimize the risk of rot.
Place the containers in a frost-free cold frame or cold greenhouse for a couple of months, or until required.
It is not necessary to lift the stools of l ate flowering varieties ; keep them in their pots in a cool greenhouse or frame at about 5°C (40°F) and in good light until required for propagation.
Charms can be over wintered in the same manner as early flowering varieties.
Commencing a new season;
Circa Week 1-2 fetch the boxed stools / pots into a heated greenhouse, water them, and keep them at a temperature of about 15°C (60°F)
Maintain a minimum air temperature of 4°C (40°F) and they will soon produce young shoots for cuttings.
| Related links; | Basal cuttings, Coldframe, Containers, Compost, Fertiliser, Heating, Planting out, Ph, Pricking out, Seed sowing, Show Schedule, Soil preparation,Watering, Q&A |
| Pests/Diseases; | White rust |
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