Chrysanthemums are invaluable for late summer and autumn borders, and come in a wide range of sizes, shapes and colours. They flower all summer long and will often be going strong until nearly Christmas, outlasting almost everything else in a cold, wet autumn, giving a real splash of colour when nothing else is in flower.
When Your Plants Arrive
Unpack plants immediately and check the compost to ensure it has not dried out in transit, water with a fine spray or sit in a tray of shallow water if the compost is dry.
Pot up as soon as possible (preferably within 24 hours) after they have had time to settle.
Potting Your Plants Up & Growing Them On
- Handle each plant by the plug root ball, rather than the stem to avoid damage
- Pot each plug into a 7.5cm (3in) pots using a good multi-purpose compost or a container compost
- Grow on for a few weeks in a greenhouse or a bright, frost-free place, but avoid direct sunlight
- Keep moist but do not over-water. If very cold weather is forecast, cover with a layer of fleece
- When the weather has started to warm up, (about mid-May) and the plants are growing away strongly, place them outside during the day to harden off, making sure to bring them in at night in case of frost
- Once there is no more danger of frost they can go to their permanent position
Preparation for Overwintering
- Cut back the main stem, after flowering, to about 20cm. So that you have a stool
- If the plant is in an exposed, poor draining or cold site it should be lifted and stored in a frost-free location during winter
- The stools should be lifted from their location and have the surplus soil shaken from the roots
- Take time to tidy up the stools. This can be done by removing any green shoots and leaves
- It is recommended to label each plant, before working on the next, as they will all start looking the same
- After tidying the stools put them into a shallow tray. The tray should have a layer of multi-purpose compost 5cm deep in
- Once in the tray give the roots a light covering of compost
- There is no need to water the stools in, soil should be kept moist during winter
- They should be stored in a cold but frost free over winter. The best places for this are usually a heated greenhouse or a cool conservatory
Decorative Spray Chrysanthemums
Always popular, outdoor spray chrysanthemums will provide plenty of long-lasting cut-flowers. Growing your own is so simple - they do not need disbudding like single bloom varieties but will benefit from being 'stopped'.
'Stopping' Decorative Spray Chrysanthemums
To ensure that several flowering shoots are produced, and to prevent the plants growing too tall, it is necessary to ‘stop’ Spray Chrysanthemums.
So, when the plants have grown to a height of about 20-25cm (8-10in), pinch out the top 5cm (2in) of the main shoot, cutting back harder if premature buds have formed.
Doing this will produce many more flowering stems, making them real value-for-money plants, flowering for months on end.
Pinch out at 3-4ft. After this, there is no need to remove any more side shoots or buds.
N.B. As the season progresses, some plants may already have been stopped once on the nursery before being dispatched.
Outdoor Bloom Chrysanthemums
You can grow beautiful Florists Chrysanthemums for yourself. They can be grown in any border and have lovely large flower-heads.
In order to get the biggest and best blooms, you need to ensure that plenty of laterals (flowering shoots growing from the main stems) are produced. To do this you will need to ‘stop’ the plants (take out the growing tip) and ‘dis-bud’ (nip out as the stems grow).
‘Stopping’ and ‘Disbudding’ Outdoor Spray Chrysanthemums:
When the plants have grown to a height of about 20-25cm/8-10in, pinch out the top 5cm/2in of the main shoot, cutting back harder if premature buds have formed.
N.B. Some plants may already have been stopped once on the nursery before being dispatched.
- Restricting the number of flowering side shoots that develop to just six
- As these flowering stems grow, small shoots will start to appear where the leaves join the stem
- These should be removed, and each stem will then produce just the one big bloom from the terminal bud
- To get the best possible blooms, remove any small, secondary buds that may develop either side of the central, terminal bud at the top of each stem
- Removal of any side shoots is best done in the early morning or evening. Take care not to damage the main stem
Hardy Garden Mums
These wonderful plants are naturally free-branching and bushy and with the minimum of pinching out will form a spectacular dome containing so many flowers they will almost obscure the foliage! They’re perfect for containers and border edges alike and will flower on and on until the first frosts. Fully hardy, they will die back over the winter to re-appear the following spring, (just cut off the old flowered stems when the new growth appears in early spring). If they are in containers remember to keep the pot protected from the frost so the roots do not freeze over the winter.
Pests and Diseases:
- Leaf miners
- Leaf and bud eelworms
- Capsid bug
- Red spider mite
- Rust diseases - Chrysanthemum white rust
- Powdery mildew
- Fungal rots