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Chrysanthemums


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The origin of the Chrysanthemum:

Evidence of Chrysanthemum growing has been found on ancient Chinese pottery dating back to the 15 th century BC.

It is believed they had many uses for them for example;


The Chinese name for chrysanthemum is Chu which led to the city of Chu-Hsien being named after the flower, the name translates to: Chrysanthemum City.


 Gold disc shaped like a Chrysanthemum flower head

Emperor of Japan's Seal

It is believed the Chrysanthemum arrived in Japan around the 8th century A.D.

Since then it has become huge symbol in the life of the Japanese people.

For example: A single flowered version has been adopted as the official seal of the Emperor of Japan.

Similarly the Imperial Order of the Chrysanthemum is the countries highest order of chivalry.

There is also a National Chrysanthemum Day, which is called the 'Festival of Happiness'.

The chrysanthemum was introduced into Europe during the 17th Century.


In 1753 Karl Linnaeus the founder of plant classification, (Taxonomy) renamed it in 1753,

He did this by combining the Greek words chrysos, meaning gold , with anthemon, meaning flower.

The earliest illustrations of mums, show them as small yellow daisy-like flower.


Development:

As Chrysanthemums were distributed throughout the world, hybridisers developed many varieties of different shapes, sizes, and colours.

Among the examples there are incurved, reflexed, anemone, and single daisy like flowers, in various shades of bronze, gold, reds, purples and white.

Some cultivars (varieties) can have different colours between their disc and ray florets (petals) and some even have different colours on the face and reverse sides of their florets.


Chrysanthemums have become widely popular because of their long lasting flowering attributes and autumnal colours.

The' Pot chrysanthemum' often referred as a 'mum' has been bred to give it a dwarfing habit making it a useful plant for growing indoors as a house plant.

The 'Florist types' can grow to around 2.5 metres (8ft) high, although the most popular varieties tend to grow to around 900 mm to 1220 mm high (3ft-4ft).

Flower sizes vary in size subject to variety, these range from around 25 mm to 250 mm (1" to 10") in diameter.

Although the Chrysanthemum is regarded as an autumnal flower, many are now grown to flower most of the year round for the Florist trade, this is done under controlled conditions by manipulating the light and temperature they receive.


Cultivation:

The Chrysanthemum belongs to the compositae family which consists of more than 200 species of hardy annuals, herbaceous and greenhouse perennials, including: Dahlias, Helianthus (Sunflower) and Zinnia

For ease of reference the data in this article has been divided into the three main chrysanthemum types, namely: annual, perennial and florist species.


Annual Chrysanthemums

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This type of chrysanthemum is useful for adding colour to a herbaceous border late in the season, and for use as 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.


Cultivationof Annual Chrysanthemums:

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 18:

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.


Perennial and Florist Chrysanthemums.

Yellow and White Blooms

Vase of Disbud Chrysanthemums

 Mainly Autumnal colours

Vase of Spray 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 flowerheads, 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.


A number of these can be seen in 'The Gallery'


Note: The classifications shown below are those laid down by The National Chrysanthemum Society in the UK.


Sections 1-12 inclusive are classified as late or November flowering varieties.

Class Number Variety Additional Classification Data
1 Large Exhibition
2 Medium Exhibition
3 Incurved Exhibition (3a) -Large flowered. (3b)- Medium flowered. (3c )-Small flowered
4 Reflexed Exhibition (4a) -Large flowered. (4b)- Medium flowered. (4c )-Small flowered.
5 Intermediate Exhibition (5a) -Large flowered. (5b)- Medium flowered. (5c )-Small flowered.
6 Anemone (6a) -Large flowered. (6b)- Medium flowered. (6c )-Small flowered.
7 Singles (7a) -Large flowered. (7b)- Medium flowered. (7c )-Small flowered.
8 Pompons (8a) -True Poms (Perfect ball of firm florets),(8b) -Semi-Poms (Half sphere with flat base)
9 Sprays (9a)- Anemone, (9b)- Pompon, (9c)- Reflexed, (9d) -Singles, (9e)-Intermediate, (9f)-Spiders, Spoons or Quills.
10 Spiders,Spoons & Quills (10a) -Spiders, (10b)-Quills, (10c)- Spoons.
11 Any Other types
12 Charms & Cascades

Sections 13-20 inclusive are classified as October flowering varieties.

This group has been produced to cater for flower 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!


Class Number Variety Additional Classification Data
13 Incurved (13a) Large flowered. (13b) Medium flowered. (13c) Small flowered.
14 Reflexed (14a) Large flowered. (14b) Medium flowered. (14c) Small flowered.
15 Intermediate (15a) Large flowered. (15b) Medium flowered. (15c) Small flowered.
16 Large October flowering
17 Singles (17a) Large flowered. (17b) Medium flowered. (17c) Small flowered.
18 Pompons True Poms (Perfect ball of firm florets), (18b) Semi-Poms (Half sphere with flat base)
19 Sprays (19a) Anemone, (19b) Pompon, (19c) Reflexed, (19d) Single, (19e) Intermediate, (19f) Spiders, Spoons, Quills(single or double)
20 Any Other types

Sections 22-30 inclusive are early flowering varieties:

An early flowering variety is a variety that blooms in the open ground before October 1st without any protection whatsoever.

This definition does not debar exhibitors from protecting blooms from weather damage (see rule 3 of the Judging manual)

Class Number Variety Additional Classification Data
22 Garden Charms
23 Incurved (23a) Large flowered. (23b) Medium flowered. (23c) Small flowered.
24 Reflexed (24a) Large flowered. (24b) Medium flowered. (24c) Small flowered.
25 Intermediate (25a) Large flowered. (25b) Medium flowered. (25c) Small flowered.
26 Anemones (26a) Large flowered. (26b) Medium flowered.
27 Singles (27a) Large flowered. (27b) Medium flowered.
28 Pompons (28a) True Poms (Perfect ball of firm florets), (28b) Semi-Poms (Half sphere with flat base)
29 Sprays (29a) Anemone, (29b) Pompon, (29c) Reflexed, (29d) Single, (29e) Intermediate, (29f) Spiders, Spoons, Quills(single or double)
30 Any Other types

Colours:

For exhibition purposes colours have been classified as listed in the panel;


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.


Colour

Bronze

Light Bronze

Pink

Pale Pink

Purple

Red

Salmon

White

Yellow

Pale Yellow

Other Colours

Code

B

LB

P

PP

Pu

R

S

W

Y

PY

O


Note to would be buyers: To ensure you are getting the colours you require it is best to purchase plants at flowering time, or to choose them from an illustrated catalogue.


Flower types

Disbud chrysanthemum: This type 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.


Early-flowering chrysanthemums: These bloom from late summer to early autumn, and are grown outdoors.


Late-flowering chrysanthemums: These are usually grown in pots outdoors in summer, and brought into a greenhouse, where they flower from autumn until late winter.


Charm varieties: Charms / mums flower from late summer to mid-autumn and are grown outdoors either in containers or in borders.

These are cultivated in a similar manner to early and late-flowering types, however, plants for exhibition need more time and attention e.g. disbudding!


Yellow Flowers

White Flowers

Purple Flowers

Purple & White flowers


Incurved chrysanthemums:

Have fully double flower heads formed with incurved petals closing tightly over the crown.

Reflexed chrysanthemums:

Have fully double flower heads formed with curved petals reflexing back to touch the stem.

Intermediate chrysanthemums:

Have fully double flower heads formed with loosely incurving petals and have a regular shape.

Single chrysanthemums:

Have flower heads with a prominent central disc, and 5 rows of flat-petalled florets.

Anemone chrysanthemums:

Single flower heads each with a dome-shaped disc, and flat, or occasionally spoon-shaped, petals.

Spray chrysanthemums:

A type of Chrysanthemum that naturally forms a number of flower heads on the same stem.


Annual programme:

For your convenience the following table is a summary of the Week Numbers indicating when essential cultural tasks on particular flower types should be carried out each season:

Task
Charms
Early Sprays
Early Disbuds
Late Disbuds
 
Week N°
Week N°
Week N°
Week N°
Put Stools on hotbed
2 - 4
2 - 4
1 - 4
1 - 4
Take Cuttings
10 - 12
8 - 10
5 - 8
5 - 8
Pot up Rooted Cuttings
14 - 16
10 - 12
10 - 12
10 - 12
Harden off Cuttings
16 - 17
14 - 15
14 - 15
14 - 15
Begin Stopping Programme
20 - 22
20 - 22
20 - 22
20 - 24
Prepare Beds / Pots*
20 - 22*
18 - 20
18 - 20
18 - 20*
Plant Out
17 - 19
18 - 21
19 - 21
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 / Cover
-
-
27 - 30
32 - 34
Potash Feed
28 - 30
28 - 30
28 - 30
32 - 35
Flowering
30 >>
30 >>
30 >>
42 >>
Lift and Store Plants
44 - 46
44 - 46
44 - 46
48 - 50


Cultivation of purchased stock - all types:


Cultivation of own saved stock - all types:

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Planting out Charm varieties:

These 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.

See table above or refer to a growers catalogue or specialist / society publication for precise timing.


Domed shaped plant brought about with good stopping techniques

Result of a good 'stopping' regime
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.

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 24.

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 to 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.


Cultivating 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 agri-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 fertiliser until the flower colour just begins to show.

Increase the temperature when they begin to flower.


Growing blooms for exhibition:

(both 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 usually 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.

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.

It may take up to three weeks for this practice to work.


Preparing for exhibition:

Note: The preparation prior to getting to the show room is as equally important as that what you will do when you get there.

Here is a list of tasks /routines to consider prior to the show:


Staging:

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.

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.

6 vases of five blooms

Single vase of five blooms

5 vases of three blooms

3 Vases of three blooms

Lifting/Storing stools:

Large trays containing lifted stools

Boxed up Stools ready for winter storage

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 late flowering varieties.

Providing the are not diseased you can 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.

Stored stools showing some basal growth

Stools on hotbed producing potential cuttings

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 15°-18°C (60°-65°F)

Maintain a minimum air temperature of 4°C (40°F) and they will soon produce young shoots for cuttings.