This month, thousands of rows of poinsettias at Alluvion Inc. Nursery / Florist in Haleiwa turned red, pink and white just in time for the holiday decorations, the culmination of a meticulous cultivation that began in July. .

The striking red variety may be the most iconic flower of the Christmas season, but she and all of her colorful cousins ​​have a temperamental reputation. It’s a delicate and tedious growing process that requires attention to detail, said nurseryman Chad Matsushima.

After several years as the head of the wholesaler’s main crop, Matsushima said, “Like children, it takes a lot to raise them. Getting a good harvest of poinsettia is always a challenge.

He feels the pain of the average shopper who can’t figure out why the leaves fall off when they bring the flower home, the whole plant is wilting, or they can’t stop those fuzzy white insects from eating it alive after Christmas.

Gardening websites list several common reasons: primarily overwatering or overwatering, sudden changes in temperature and humidity, and too much or too little sun.

Matsushima nodded sympathetically and offered some tips on how to make poinsettias last during the holiday season. “Pick one that looks good to start,” switching to plants with yellowing leaves, sparse leaves on the bottom, or broken branches.

Water two to three times a week to keep the plant from drying out completely, he said. It needs to be watered when the top 1 or 2 inches of the soil is dry and the pot is light. Remove it from the foil or foil and let the excess water drain into the kitchen sink so that the roots don’t get stuck in the water and rot, he said. declared. But it’s also important to let the poinsettia dry out a bit between waterings, Matsushima added.

Alluvion grows his poinsettias in shade canvas tents because they like indirect light, so he recommends placing them near a window. Some people grow their poinsettias outdoors and bring them indoors for the holidays, but some plants may not turn out well.

He doesn’t have experience growing plants all year round, but the conventional advice is to prune the plants in April and August, he said.

At Alluvion, “every year we start over” with new cuttings from the mainland, Matsushima said. It begins planting after July 4 and completes most of it in the first weeks of August.

Plants are very susceptible to insects and disease, and are particularly vulnerable to whiteflies – “it’s a battle”. They should be sprayed for both if necessary and fertilized with a 20-20-20 formula. Branches should be pinched to induce fuller leaf spread, and their height should be controlled in proportion to the size of the pot. Taller plants should be staked and supported with twine.

Once they’re ready to be sold – the first batch in mid-November – they require careful handling to avoid damage, sometimes involving boxes or paper wrappers for delivery, especially to neighboring islands. .

THE NURSERY started growing poinsettias 15 years ago, becoming one of Oahu’s top growers, said Susan Matsushima, Chad’s mother. She founded the company in 1996 and today deals with flower arrangements. They learned how to grow poinsettias from another grower who later joined the business, but now “it’s Chad’s baby,” she said.

This year, Alluvion produced 18,000 poinsettias, most of which resold to stores, hotels and businesses statewide, said Chad Matsushima. The best-selling item is a red poinsettia in a 6 inch pot.

Poinsettias begin to change color with cooler temperatures and longer nights as part of a natural cycle – the first ones around the end of October this year. It takes three to four weeks for the bracts to reach their full color, he said. Bracts are the leaves that take on color, not the flower itself.

(The real flowers are the tiny yellow buds, called cyathes, that can be seen in the center of each rosette of colorful bracts, according to a 2009 University of Hawaii Agricultural Extension Service report.)

Smaller, more bushy plants last longer, in terms of hardiness and attractiveness, than taller, longer plants, Matsushima said. The company offers five varieties of red, each of which changes color at different times during the season; they don’t want all the plants to change color at the same time as they have to be able to meet customer demand throughout the long holiday season.

The nursery does not have to trick the bracts into changing color. According to conventional wisdom, this is achieved by keeping the plants in the dark. Hawaii has an average of 12 hours of darkness from September to December, and Alluvion is in an area with little exposure to a lot of house and street lighting at night.

However, the UH Farm Report gave this advice to get poinsettias to change color:

“The colorful bracts only form when the nights are long – 12 hours or more. This means that the plants should not be exposed to light at night after September 21. They should be in a dark place, completely away from street lights or house lights. If you don’t have a completely dark area outside, you can place them in an unlit room, closet, or light-proof box every evening for at least 12 hours.

“They also need full sun during the day, so be sure to bring them back to a sunny spot outside after they’ve been in the dark. Depending on the variety you’re growing, you should start to see colorful bracts. in 6 to 9 weeks. Continue monthly fertilizer applications until true flowers (cyathia) develop. The plant does not need to be kept in the dark or fertilized after true flowers. appear.

The report concludes: “You may find that this process takes a long time! If so, it’s always a good idea to support your local nurseries and buy fresh poinsettias each year.

And surprise: the Matsushima completely agree. Smiling, Susan Matsushima said, “We don’t want people growing poinsettias all year round -” Her son finished: “- We want them to buy new ones next year! “

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Alluvion inc.

61-676 Kamehameha Hwy., Haleiwa

Info: 637-8835; alluvionhi.com

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