A bouquet that still looks decent on day eight feels like luck. Mostly, it is not. Cut flowers fade for three reasons: bacteria multiplying in the water, air blocking the stem's drinking channels, and warmth speeding everything up. Get those three under control and most bouquets will comfortably give you a week or more.

None of it takes long. Most of the work happens in the first ten minutes after the flowers arrive, and in two-minute checks after that.

Start with a genuinely clean vase

Rinsing is not cleaning. A quick swill under the tap leaves behind the biofilm bacteria love, and your flowers pay for it from day one.

• Wash the vase in hot, soapy water, using a bottle brush to reach the base and sides. The bottom few centimetres matter most.
• Rinse thoroughly — detergent residue damages stems.
• If the vase has held old water for a while, soak it in a diluted bleach solution, then rinse until you cannot smell bleach at all.
• Choose glass or ceramic over metal if you are using flower food; metal can react with it.

Do this before you touch the flowers, so the vase is ready the moment the stems are cut.

Cut the stems at an angle, with something sharp

Flowers are usually out of water for hours before they reach you, so the first cut matters most. Take at least three to four centimetres off each stem with sharp secateurs or a sharp knife. Blunt scissors crush the stem ends, and crushed tissue cannot take up water properly.

Cut on a slant of about 45 degrees so the stem does not sit flat against the bottom of the vase, where it will seal itself shut. If it is easy to do, cut under water — a bowl in the sink works — which stops air being drawn into the stem. Remove every leaf that would sit below the waterline, because submerged foliage rots quickly and turns the water sour.

Then repeat the cut every two days. A fresh centimetre off the ends takes seconds and noticeably extends vase life.

Use the flower food — it does three jobs at once

That little sachet is not a gimmick. It contains sugar to feed the buds, an acidifier to help water move up the stem, and a biocide to slow bacteria. Doing all three at home is fiddly, so use the sachet if you have one, mixed into the amount of water stated on the packet. Too little water makes the dose too strong.

If the sachet has gone missing, a rough substitute is a teaspoon of sugar and a few drops of household bleach per litre of water. Bleach is a household chemical: handle it carefully, keep it well away from children and pets, and never mix it with other cleaning products. Sugar on its own, without the biocide, feeds bacteria rather than flowers.

When you change the water, make up a fresh solution rather than topping up the old one.

Keep them cool and away from the fruit bowl

Most cut flowers last longest at around 16–20°C. Radiators, sunny windowsills, the top of the fridge and draughty doorways all shorten their life, and direct sun is worse than any of them.

The fruit bowl is the quiet culprit. Ripening fruit releases ethylene gas, which speeds up ageing in flowers, and bananas are the worst offenders. Move the bowl or move the vase — a metre of distance helps more than you would expect.

A cool room overnight does a lot of good, so if you have a spot a few degrees cooler, put the bouquet there before bed. A domestic fridge is usually too cold for most flowers, and one shared with fruit and vegetables does more harm than good. Skip misting the blooms, too: water sitting on petals encourages brown patches and grey mould, especially in a still room.

Change the water, then check the vase daily

Cloudy water means you have left it a day too long. Empty the vase completely — topping up a cloudy vase just dilutes the problem — rinse it, re-cut the stems and refill with fresh water and food. Every two days is a good baseline, daily in warm weather or if you notice a smell.

Keep the water level sensible: enough to cover the bottom five to eight centimetres of stem is plenty. Deeper water does not help, and it makes the ends rot faster. While you are there, spend a minute on this:

• Feel the water for slime and smell it for sourness. Either one means change it now.
• Pick out fallen leaves and petals, which rot quickly.
• Lift out any flower with a drooping head or browning petals, so it does not drag the rest down.
• Trim anything that has slipped below the waterline.

Some flowers need a slightly different approach

A few varieties behave differently enough to be worth knowing about.

• Tulips keep growing in the vase, so they will lean and shift over a few days. That is normal, not a sign of decline. They prefer cold water, a shallow fill and a spot out of direct sun. A fresh cut and cooler water will often perk up a drooping tulip.
• Daffodils release sap that harms other flowers. Keep them in their own vase, or stand them in water alone for a few hours before mixing them with anything else, then re-cut and add them to the arrangement.
• Woody stems such as lilac, forsythia and flowering cherry drink slowly. Split the bottom couple of centimetres with a sharp knife, or give the ends a gentle crush, and use lukewarm rather than cold water.
• Hydrangeas lose water through their petals and wilt faster than most. If the head flops, re-cut the stem and float the flower head in cool water for 20–30 minutes before returning it to the vase.

A routine that takes five minutes a week

Flowers do not need much, but they need it regularly. Trim and re-cut the stems the day they arrive, mix fresh food solution, put the vase somewhere cool and away from fruit, then change the water every two days and pull out anything past its best. That is the whole method.

Do those things and a good bouquet will usually give you a week to ten days, with chrysanthemums, alstroemeria and carnations lasting longer still. When the last bloom finally goes, clean the vase properly before it returns to the cupboard, and the next bouquet starts with a clean slate.

Photo: Pezibear / Pixabay