Conditioning involves the preparation of cut plant material prior to its arrangement, to ensure that its life is not unduly shortened. Correct conditioning will make sure that flowers and foliage last for the maximum time, providing the most value and enjoyment.

One of the most common causes of wilting in cut flowers and foliage is the presence of an air-lock in the stem. The air-lock usually forms as the flower is cut, when atmospheric pressure forces air into the water ducts of the stem in which there is normally a partial vacuum. It is virtually impossible to prevent the ends of dry-packed flowers and foliage from drying out during transit from the grower to the wholesaler, and from the wholesaler to the Florist. For this reason, many flowers are now shipped with their stems in a few inches of water. Flowers cut from the garden and left for any time before being conditioned will also form an air lock, so always carry a bucket of water with you into the garden, so that you can place the plant material into water immediately, on a temporary basis, thus preventing the stem ends from drying out.

All plant material should be unpacked as soon as possible after buying from the florist, and any plastic sleeves and elastic bands should be removed. If cutting flowers and foliage from the garden, the best time for cutting is early morning, or late evening. This is the time when flowers have the maximum amount of water in their stems, and they will condition more readily. Cutting in the heat of the day allows the material to wilt much quicker. Whether flowers are bought from the florist, or picked from the garden, all lower leaves should be removed from each stem, as any leaves left under water when conditioning will quickly begin to rot and cause a build-up of bacteria which will clog the stem ends, preventing the uptake of water, as well as causing the water to smell foul.

All buckets used for conditioning should be meticulously clean, and should be cleaned out regularly, to prevent the build up of bacteria. After removing the lower leaves, all stem ends should have the bottom " - 1" removed at a sharp angle, thus exposing more of the central area of the stem, known as the xylem tissue, which is responsible for the uptake of water. As a general rule, buckets should be filled to about full with warm water, to which cut flower food has been added at the appropriate rate. This will prolong the life of the flowers, and helps to prevent bacterial growth. Using warm water allows the water to enter the stem more rapidly, so conditioning is quicker. However, use cool water for bulb flowers, unless you want them to open quickly. Flowers and foliage should be left in the water for at least two or three hours, and preferably overnight, before arranging them.

One important thing to remember is that stem ends should never be hammered, as this causes damage to the tissues, which leads to a build up of bacteria, thus shortening the life of the material.

Plant material should be conditioned according to its stem type, and conditioning varies with different stem types:-

Woody Stems (E.g. Roses, Mimosa, Eucalyptus, Beech, Yew, Pittosporum, etc.)

Stems should be cut at a sharp angle, and the stem ends split for about ". Remove all the lower foliage which will be below the level of the water, and place the stems in a bucket about filled with warm water, to which cut flower food has been added at the appropriate rate.

Semi-Woody Stems (E.g. Chrysanthemum, Lily, Carnation, Leatherleaf, Asparagus Fern, etc.)

These should be conditioned by cutting the stem ends at a sharp angle, removing all the lower foliage which will be below the level of the water, and placing the stem ends in a bucket about filled with warm water, to which cut flower food has been added at the appropriate rate. Special flower food is available for Lilies, and this should be used if possible.

Soft Stems (E.g. Freesia, Hellebore, Anemone, etc.)

Condition as above, but deeper water should be used so that the flowers are immersed up to their necks. After a good overnight drink, the flowers can then be arranged. Hellebores are a special case and benefit from the boiling water treatment - see special notes below for details.

Hollow Stems (E.g. Delphinium, Lupin, etc.)

Hollow stems are notorious for forming air-locks, as air enters the stem as soon as it is cut. Cut the stems at an angle and remove lower leaves as usual. Turn the stems upside down, and fill the hollow stem with tepid water. Plug the stem with cotton wool, or hold your thumb over it until it is placed in the bucket.

Milky Stems (E.g. Poppy, Euphorbia, Poinsettia, Ficus, etc.)

The stems of some flowers exude a milky substance, called latex, when cut. This can be messy, and also can be an irritant if it comes into contact with the skin. Therefore, plant material in this category should have the stem ends cut, and then the end should be burnt in a flame for a few seconds, to seal it. The cut stem ends can also be rinsed under running warm water to remove excess latex, before placing into warm water for conditioning.

Bulbous Stems (E.g. Daffodil, Tulip, Bluebell, Hyacinth, etc.)

Most bulbous stemmed flowers are pulled, not cut, from the plant by the grower. This means that the end of the stem is often white and firm. The stem will often not drink from this white area, therefore, it should be removed completely, by cutting at an angle, as water can only be absorbed through the green part of the stem. Bulb flowers should be conditioned in cool to tepid water, unless the flowers are wanted open, as warm water speeds up the development of bulbous flowers. Special flower food for bulb flowers is available, and should be used if possible. **Special Note - Daffodil stems exude a poisonous sap when cut. This will shorten the life of other flowers if Daffodils are conditioned in the same water.** Therefore, they should always be conditioned separately. If they are being arranged in water, they should be arranged separately, but if being arranged in floral foam, this is not necessary, and they can be arranged together with other flowers.

Special Notes for certain types of material:

Hellebores and Hydrangeas are notoriously difficult to condition when very fresh. Both will benefit from boiling water treatment as follows: Add about an inch of boiling water to a jug, then place the stem ends in the water for around 1 minute. This will force out the air from the stems and allow better uptake of water. Take them out of the hot water, then re-cut the stem ends and put them into water up to their necks or immerse them completely overnight before arranging. A more foolproof method for Hellebores is to wait until they have formed (or are beginning to form) seed pods. At this stage they will condition very well and last a long time. For Hydrangeas, it is better to wait until they are mature and turning slightly papery before picking as very young flowers often don't condition well.

Shiny or smooth foliage should always be washed, as this removes any dirt and dust. It's also a good idea to use a leaf-shine product, thus enhancing the appearance.

Single leaves can be completely immersed in water to condition them.

Grey foliage such as Santolina or Senecio, or woolly foliage such as Stachys lanata should never be fully immersed to condition it, as the water is absorbed by the grey covering and the colour of the foliage would be spoiled. Also, absorbed water can be siphoned by these leaves, creating pools of water outside the container.

Very new growth, such as spring foliage, should not be used, as it is very difficult to condition, and does not last well.

Flowers which sometimes wilt even after conditioning, (roses, for example), should have their stems re-cut, and the stem ends placed in about 1 inch of very hot or near-boiling water. This destroys the air lock, and enables the plants to take up water again. The heads of the flowers should be wrapped in tissue paper or newspaper to protect them from the steam. When the flowers have revived, (usually after to hour) re-cut the stem ends, as the boiling water will have damaged them, and continue to condition overnight before re-arranging them.

Carnations and pinks should have their stems cut between the node or joint, as they cannot take up water if cut or broken on the node.

Tulips should be wrapped in newspaper when conditioning, to keep the stems upright, as Tulips tend to "do their own thing" when being conditioned. Tulips continue to grow after being cut, and can grow up to 1" per day. They will always turn towards the light as well, and the flowers will turn upwards if arranged horizontally or almost horizontally. This should be taken into account when using tulips.

Some flowers, such as Gladioli, will always turn upwards at the tip if not arranged vertically. (For the botanically minded, this is a phenomenon called "negative geotropism" whereby the stem tips always turn away from gravity. Roots are positively geotropic, therefore, they will always head towards gravity!) One way to avoid this happening is to carefully pinch out the top few buds, as it is only these which are affected.

Clematis, Violets and Hydrangea benefit from complete immersion of the flowers to condition them.

Lilac, Azalea, Philadelphus, Forsythia, Rhododendron, and other woody flowering stems, should have all the foliage removed, as it prevents sufficient water from reaching the flower head.

Lilies should have their stamens removed before the pollen forms, to prevent staining of the petals, or clothes and furnishings.

Mimosa should have the flower heads covered in a plastic bag whilst being conditioned, to prevent drying out.

Sweet peas, Pansies and Primroses should not be sprayed with water, as this can disfigure the petals.



Site developed and maintained by Chrissie Harten
Words and pictures Chrissie Harten, 2009.