An outdoor event in Texas heat: which flowers hold up and how to plan around the sun

Plan for the heat first and the flowers second

For an outdoor event in Texas heat, choose sturdy flowers such as orchids, anthurium, ginger, bird of paradise, protea, carnations, chrysanthemums and succulents, and save delicate ones like hydrangeas, peonies, tulips and gardenias for indoor or cooler events. Even more important than the variety is timing and placement: keep flowers cool until the last possible moment, keep them in water, put them in shade and schedule the outdoor part of the day for when the sun is lower. A sturdy flower in direct afternoon sun will still struggle, and a delicate one in the shade at dusk can look lovely.

I have designed flowers for weddings, private parties and corporate events at Willow Creek Florist in Dallas since 1988, and North Texas summers have taught me to plan the flowers around the weather rather than hope the weather cooperates. Here is how to do that.

What a hot afternoon does to a cut flower

A cut flower is losing water from the moment it is harvested. Susan Han of the University of Massachusetts, in her extension article on handling cut flowers, explains that harvested flowers continue to transpire and wilt rapidly, that temperature management is the most critical factor for their quality, and that, generally, the lower the temperature, the longer flowers last.

Heat speeds up everything that shortens a flower's life. Petals lose water faster than the stem can replace it, flowers open and pass their peak sooner, and the water in a vase warms up and grows bacteria more quickly. Add sun and wind, and an arrangement can lose in an afternoon what it would lose in several days indoors.

That is why the plan for an outdoor event is really a plan for keeping flowers cool, shaded and drinking for as long as possible.

The container matters as much as the flower. A larger vessel holds more water, which warms more slowly and gives stems more to drink through a long evening. Arrangements in floral foam need the foam fully soaked before they leave the shop and topped up on site, because foam that dries in the heat cannot keep the flowers alive. For centerpieces outdoors, I prefer designs with a generous water source over tight, shallow ones.

Flowers that tend to stand up to a hot day

In my experience, these are the flowers I reach for first when an event is outside in warm weather. Many tropicals come from hot climates in the first place, and the sturdier garden flowers have firm petals and stems that hold their shape.

Color helps, too. Strong, saturated colors still read well after a long day, while pale, papery petals show every bit of wilting and browning. And greenery is not just filler at an outdoor event: sturdy foliage shades the flowers around it, holds the shape of the arrangement and keeps the design looking full even if one bloom tires.

• Orchids, especially sprays of dendrobium and oncidium
• Anthurium, ginger and bird of paradise
• Protea and other firm, textural flowers
• Carnations and chrysanthemums, which are tougher than their reputation
• Alstroemeria, sunflowers and zinnias
• Succulents and sturdy foliage for texture and structure

Flowers to save for the ballroom or a cooler month

Some of the most romantic flowers are also the thirstiest and most delicate. I love designing with them, but I steer clients away from using them in full sun on a hot day, or use them only in arrangements that will sit in shade with plenty of water.

• Hydrangeas, which lose water quickly through their large heads
• Peonies and garden roses, which open and pass their peak fast in heat
• Tulips, sweet peas and anemones
• Gardenias and other flowers that bruise and brown easily
• Any flower used out of water, such as in a hair piece or a boutonniere, for long periods

Timing and placement matter more than the variety

The single best decision for outdoor flowers is the time of day. A ceremony at seven in the evening is a different problem from one at two in the afternoon. If you have any choice, schedule the outdoor portion for later in the day and move the reception indoors or under cover.

Then think about where each arrangement will sit. Tables under a tent, a tree or a pergola protect flowers from direct sun. Arrangements on the west side of a patio take the worst of the late afternoon sun. Wind dries flowers and knocks over tall designs, so heavier, lower containers are safer outdoors.

Finally, shorten the time flowers spend outside before guests arrive. We keep arrangements cool in the shop and in the delivery vehicle, and for outdoor events we set up as close to the start time as the venue allows, placing the most delicate pieces last.

For a summer event in Dallas, a tent alone is not always enough. If the reception is under canvas in July or August, ask whether the tent will have fans or air conditioning, and whether the sides can be opened for airflow. Those choices protect your guests as much as your flowers, and they make it possible to use more delicate varieties on the tables.

Bouquets and boutonnieres in the heat

Personal flowers have the hardest job, because they spend hours out of water and close to warm hands and bodies. Choose sturdier flowers for boutonnieres and corsages, and keep them in a cool room until the last moment before they are pinned on.

Bouquets should go back into water whenever they are not being carried. Ask your planner or a bridesmaid to keep a vase of cool water ready in the shade during photos and the reception. Schedule outdoor photos for the early evening when you can. If the ceremony is long and the sun is strong, a bouquet built in a holder with wet floral foam, or made with hardier flowers, will look better in the last photo of the night.

Flower crowns, hair flowers and floral jewelry face the same problem, with even less help. Use the sturdiest flowers for anything worn, make them as late as possible, keep them in a cool room in a closed box with a little moisture, and have a spare for the bride or the honoree in case the first one tires before the last photo.

Keep the flowers away from exhaust, grills and generators

One threat people rarely think about is invisible. Han's article explains that ethylene, a colorless, odorless gas that acts as a plant hormone, is produced in large quantities when organic matter such as gasoline, firewood and tobacco burns, and that certain cut flowers are very sensitive to it. Responses include flowers dropping, buds failing to open and flowers dying early.

At an outdoor event, that means generators, idling vehicles, smokers' areas, grills and fire pits are all poor neighbors for arrangements. Ask the venue where generators and catering equipment will be, and place flowers upwind and well away from them.

The same caution applies before the event. Flowers left in a running vehicle while someone unloads chairs, or stored next to the catering truck, can be exposed before a single guest arrives. A few minutes of planning about where the flower setup area will be keeps the arrangements clear of fumes from start to finish.

When permanent flowers are the smarter choice outdoors

For pieces that must sit in full sun for hours, such as an arch at an outdoor ceremony site, garlands on a fence or decor installed early in the day, a high-quality permanent design can look better at the end of the event than fresh flowers would. Blending a silk base with fresh accents at eye level is another option: guests see and touch the fresh flowers, while the structure holds up to the sun.

I explain where each kind works best in my guide to choosing silk or fresh flowers. For an outdoor event, the rule is simple: fresh where people are close, permanent where the sun is strongest.

The other North Texas extreme: a sudden cold night

Heat is the usual worry, but our winters bring the opposite problem. Han's article notes that flowers from tropical and subtropical regions develop chilling injury below 50 degrees Fahrenheit, with symptoms such as darkened or water-soaked petals, and names anthurium, bird of paradise, heliconia and certain orchids among them.

So the tropicals that are perfect for an August patio party are a poor choice for an outdoor event on a cold December evening, or for arrangements left in a car or on a loading dock overnight in winter. For cool-weather outdoor events, roses, carnations, chrysanthemums and evergreen foliage are more forgiving.

How we plan the flowers for an outdoor event

When you call about an outdoor event, I will ask for the date, the time of day, the venue and exactly where the ceremony, cocktails and reception will happen, including what is in shade and what is not. From there, I suggest flowers that will hold up in those conditions, design arrangements that sit low and steady, keep everything cool until setup, and time delivery to the event rather than the venue's opening hour. We work with you from the first consultation through the event itself.

If you are thinking of doing some of the flowers yourself, my guide to DIY wedding flowers versus hiring a florist explains which pieces are realistic. And for keeping arrangements fresh after the event, when centerpieces go home with guests, the steps in making fresh flowers last apply. Plan for the heat, and the flowers will still look right when the last guest leaves.

Questions people ask me