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If left alone, the latex on poinsettia leaves will dry into a small, dry spot that can sometimes be carefully and gently picked off.

Courtesy Meredith Seaver, USU Extension

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Jostling or brushing against a poinsettia can cause latex to leak from the leaf. Display poinsettias where they will be far enough away from foot traffic to avoid damage.

Courtesy Meredith Seaver, USU Extension

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The most effective control methods are used while the grasshoppers are small nymphs. By the time grasshoppers are mature, they are less susceptible to insecticidal sprays and other control methods.

Courtesy Meredith Seaver, USU Extension

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Grasshoppers also will lay eggs in the soil of potted plants and container gardens. Dump out and inspect the soil or cover the soil in the early spring with sticky trap cards to prevent those eggs from becoming a problem.

Courtesy USU Extension

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Last year, my poinsettia kept getting crusty white spots on the leaves. Most of the time they weren’t very big, and the plant didn’t have any other problems, but I don’t want this year’s plant doesn’t get the same disease.

You’ll be glad to know that your poinsettia didn’t have a disease. From your description, it sounds like your poinsettia had some small leaks of latex on the leaves. The fluid in poinsettias is high in latex and it sometimes erupts onto the leaf surface. If the small beads of latex are left untouched, the latex will dry into small crusty spots that can sometimes be carefully picked off.

The most common cause of latex leaks in poinsettias in a home setting is mechanical damage — something brushes against the leaves or the poinsettia is jostled, causing a tiny break in the leaf. You can reduce this problem by placing your poinsettia where it will be away from foot traffic and by handling your poinsettia carefully when you’re relocating the plant or watering.

If any readers are growing poinsettias in a hobby greenhouse, they may have experienced a similar problem called latex eruption or poinsettia crud. It’s related to greenhouse growing practices, especially greenhouse temperatures and watering habits. High moisture pressure in the plant can cause cells to rupture, forcing latex out of the plant cells and onto leaf surfaces and damaging surrounding tissues.

Here are some tips for preventing latex eruption problems in hobby greenhouses, but they’re also basic good poinsettia care practices for home poinsettias.

• Let the soil dry down a bit between waterings. If the pot feels heavy and the soil surface is moist, it isn’t time to water yet. When you do water your poinsettia, water deeply so that the entire pot of soil is moistened and at least some water drains from the container.
• Water early in the day. Wet soil during the night increases the likelihood of increased fluid in the plant and latex eruption.
• Don’t crowd your plants together on your greenhouse bench or in your home. Make sure there is good air circulation in the area where you have your poinsettia displayed, but avoid putting your plants close to drafty windows, doors or furnace vents.
• Avoid high or low temperatures. The best temperature for poinsettias is between about 60 degrees and 70 degrees, with the nighttime being cooler than the daytime.
• Handle your poinsettias gently.

Reducing grasshopper populations

Grasshoppers are always a nuisance. But in the last several years, they have invaded our landscapes, backyard gardens and small farms in very large numbers. Fortunately, we can take a little break from our grasshopper struggles for now, but we shouldn’t assume we won’t see these pests again next year.

Grasshoppers had good conditions for egg laying this fall, but winter conditions and very early spring conditions will affect how high the population will be next year. A cool, wet spring plus natural pathogens will reduce successful egg hatch. A mild winter, warm, dry early spring and drought conditions will favor a higher grasshopper population.

We can’t do anything about the weather, and we can’t control how our neighbors manage their landscapes, but that doesn’t mean we can’t take steps to reduce the egg hatch on our own properties.

Grasshopper eggs are laid about 1/2 inch to 2 inches down in the soil where they’re hidden away from most predators. Two passes of fall tillage wherever you can safely turn the soil (best when soils aren’t wet) will expose the egg cases to the elements and make it easier for predators to find them.

It may surprise you to learn that grasshoppers will also lay their eggs in container gardens. Dump out containers that are going to be replanted in the spring and check for egg cases. If you have containers with perennial plantings that can’t be turned out, you can protect them by laying sticky trap cards over the soil to catch the new nymphs as they hatch in the spring.

Check back in the spring for tips on steps you can take to protect your yard and garden plants next year.