How Much Water Do Flowers Need in a Vase?

Most cut flowers need a vase filled about two-thirds full, so that 10-15 cm of each stem sits under water and no leaves are submerged. Woody and thirsty flowers such as roses, hydrangeas and lilac like it deeper, while soft, hollow stems such as gerberas, callas and anemones do better in just 5-7 cm of water. Whatever the depth, the level has to stay there, which means topping up daily.

That is the short answer. The useful part is knowing why the rule bends from flower to flower, how much a fresh bouquet really drinks in its first day, and what water does to stems when there is too much or too little. Here is how a florist thinks about it, with practical numbers you can use at home.

The basic rule: depth matters more than volume

People often ask about millilitres, but flowers do not care how much water is in the vase overall; they care how much of the stem is in contact with it. A stem drinks through its cut end, and the deeper that end sits, the longer it stays in water as the level drops. For an average mixed bouquet with stems 40-60 cm long, that means a vase filled to about half or two-thirds of its height.

There is one hard limit: no leaves below the waterline. Submerged leaves start to rot within a day, the water turns cloudy, and bacteria quickly clog the stem ends so the flowers can no longer drink. Before filling the vase, strip every leaf from the part of the stem that will be under water. If a vase is so tall that you would have to strip half the greenery, use a shorter vase rather than less water.

A simple way to check: after arranging, look through the glass. You should see clean stems, clear water and a gap of several centimetres between the water surface and the lowest leaf.

Flowers that want deep water

Roses, chrysanthemums, carnations and alstroemeria are happy at the standard two-thirds level. Roses are especially sensitive to air bubbles in the stem, so a generous depth and a fresh angled cut under running water help them avoid the drooping head that people call bent neck.

Woody and semi-woody stems need even more. Lilac, viburnum, flowering branches and hydrangeas move a great deal of water and struggle in a half-empty vase. Hydrangeas are the champions: they lose moisture through their large heads, so give them a vase filled almost to the top, and if a head wilts, submerge it whole in cool water for half an hour.

Tulips are a special case. They are thirsty and keep growing in the vase, often adding several centimetres. Give them a tall vase with a good depth of cool water, and expect to top up more often than for any other spring flower. Peonies also drink heavily as they open, so check them morning and evening.

Bouquets we can deliver

Bouquet of 1 yellow sunflowers

$13

Bouquet of 3 white French roses with eucalyptus, 50 cm

$18

Bouquet of 3 red French roses with eucalyptus, 50 cm

$18

Bouquet of 3 pink roses with eucalyptus, 50 cm

$18

Flowers that prefer shallow water

Soft or hollow stems behave differently. Gerberas, callas, anemones, ranunculus and amaryllis have stems that soften and rot if they stand in deep water for days. For these, 5-7 cm of water is enough. The flowers still drink well, and the stems stay firm much longer. With gerberas, a shallow vase also stops the heads from bending, because the stem below the water does not get soggy.

Daffodils and other narcissi want shallow water for another reason: their stems release sap that harms other flowers. If you mix them into a bouquet, keep them in a separate shallow vase for a few hours first, then rinse the stems and add them without re-cutting.

If your bouquet mixes deep-water and shallow-water flowers, aim for the middle: around a third to half of the vase, with frequent small top-ups instead of one big fill. That keeps the roses drinking and the gerberas firm.

How much a bouquet drinks, and how often to top up

A fresh bouquet is at its thirstiest in the first 24-48 hours. A medium bouquet of fifteen to twenty-five roses can easily take up several hundred millilitres on day one, especially in a warm, dry room with the heating on. That is why a vase filled perfectly in the evening can be half empty by morning, and why the most common reason for a bouquet wilting on day two is simply that it ran out of water overnight.

Check the level every morning for the first few days and top up with fresh, cool water to the original mark. Topping up is not a substitute for changing the water, though. Every two days, empty the vase, rinse it, trim the stems by 1-2 cm at an angle and refill. Our florists' schedule for vase water changes explains how often to do this for different flowers.

Keep the bouquet away from radiators, direct sun and fruit bowls. Heat makes flowers drink faster and evaporate more, and ripening fruit releases ethylene, which speeds up wilting. A cool spot can easily add several days to the life of the same bouquet with the same amount of water.

Water quality: temperature, cleanliness and flower food

The right amount of water will not help if the water itself is wrong. Use a vase washed with hot water and a drop of detergent; bacteria left from the previous bouquet are enough to block new stems in a day. For most flowers, room-temperature or slightly cool water is ideal, while woody stems and wilting roses often respond to lukewarm water. We go through the details in our guide to the best water temperature for cut flowers.

If the bouquet came with a sachet of flower food, use it and dissolve it in the amount of water stated on the packet. Too little water makes the solution too strong, which can burn stem ends; too much dilutes it. Without flower food, clean water changed regularly works perfectly well. Skip the folk remedies such as aspirin, sugar or coins: they either do nothing or feed bacteria.

Soft tap water is fine for almost all flowers. If your water is very hard or heavily chlorinated, let it stand for a few hours before using it, or use filtered water for top-ups.

Sending flowers to Russia: a care note goes a long way

If you are ordering a bouquet for someone in Russia, the advice above is worth passing on. A free card comes with every Turboflora order, and a line such as fill the vase two-thirds and top up every morning fits easily under your message. Delivery is anonymous by default, so if you want the recipient to know who sent it, sign the card.

Choose a format that suits the recipient as well. Someone who travels a lot or forgets to check the vase will do better with a hat box in wet floral foam, which only needs a top-up every couple of days. You can browse both formats in our bouquets catalogue. City delivery costs 500 RUB; for remote districts and suburbs the operator confirms the price when confirming the order. Express delivery in large cities takes 1-2 hours after confirmation, or you can choose an exact time, a time window or pre-order up to 30 days ahead.

The courier calls the recipient about 15 minutes before arrival, so the flowers go into water quickly. To agree the time, address and card text, or to get a photo of the bouquet before delivery, message a manager on WhatsApp. Payment is online by bank card, SBP or Yandex Pay. We deliver bouquets across Russia in 1–2 hours.