Studies show poinsettias aren't poisonous

Question: Are poinsettias poisonous?

Answer: There is a myth surrounding poinsettia leaves and how poisonous they are.

When I was a student at the University of Minnesota, one of my professors who was a floriculture specialist, tried to dispel this myth by appearing on local television.

While on television, he ate the flowers, which are really colorful leaves or bracts. They can be considered very mildly toxic if eaten in enough quantity. They are not particularly tasty and so you really have to be dedicated to get past the first couple of chews.

Our own Linnis Mills appeared on television and did a similar demonstration.

Old myths die hard and they will still probably persist. However, eaten in enough quantities, I'm sure that it would make you sick.

Instead of worrying about whether a poinsettia can harm you, I'd be more concerned about all that fattening and unhealthy food we digest during the holiday season.

Q: How can I keep my Christmas tree alive as long as possible?

A: Technically the tree is dead as soon as it is cut at the farm or plantation. What you really want to know is how I can keep the needles on as long as possible. There is another myth or myths circulating about needle retention on Christmas trees. These have to do with the ingredients to use in the water poured in the tree stand. Some of these home ingredients are sugar, bleach, aspirin and other concoctions. The unsupported reasoning behind these is that sugar is supposed to supply energy to the branches and help retain needles.

In cut flowers held in a vase of water, bacteria begin to grow inside the water conducting vessels in the stem and plug them up. This causes early wilting of the flowers. Chlorine or other bacteria-killing ingredients are sometimes recommended to reduce this bacterial growth and prolong the time to wilting and flower life.

Just this last year, an article appeared in a horticulture research journal comparing some of these home brews and evaluating their effectiveness. The conclusion was that nothing was better than just plain old tap water. My recommendations are to buy the freshest cut tree you can find. Ask when they came in and where they came from. Trees from colder climates probably will last a little longer, all other factors being the same. Follow the instructions from your Christmas tree vendor and make a fresh cut. Whether you want to add those extra ingredients is up to you.

Q: I don't like cut Christmas trees. What trees are good for living Christmas trees that can be planted later?

A. There are several precautions you need to take if you are purchasing a living tree. First, where are you going to plant it after Christmas? Most of the trees sold as living trees grow to be huge plants. Some of them might reach 60 to 70 feet or more. Do you have the room for these plants? Will huge trees eventually look funny planted next to a single story home? Big trees will eventually use more water than smaller trees. Are the trees suitable for our climate? Check with our Master Gardeners or the Desert Demonstration Garden if you're not sure. Could you donate your tree to your city or county park's department or the school district instead of your yard? The budgets for these departments are usually meager and they may appreciate the gift if you could transport it for them.

Living Christmas trees should be kept inside the home the shortest time possible. As soon as those plants are put into the warm temperatures inside the home, they may think that it's spring and put down some of their defenses against the cold. Living Christmas trees are a good option for the homeowner, opposed to cut trees, but it does need some forethought or it might be cruel and counterproductive to the plant you are trying to save.

Q: Last winter my fescue lawn didn't look very good in January. Is there something I need to do to prevent this from happening this winter?

A: Fertilizing your lawn before mid-December with a high nitrogen fertilizer is the best way to keep your lawn as green as possible this winter.

We always suggest fertilizers having a 3-1-2 or 4-1-2 ratio for the lawn. Examples would be fertilizers with a 21-7-14 or 20-5-10 grade on the bag. This provides the right balance of nitrogen, phosphorus and potassium for lawn grasses.

A high percentage of the nitrogen, the first number, should be slow-release for more even growth. You can reduce the amount of fertilizer on the bag up to one-half if you are using a recycling mower or are on our Don't Bag It lawn care program. Imagine that! Save money on fertilizers and reduce your work and mowing time by 40 percent by recycling your clippings instead of throwing them in the trash.

The only other thing I might suggest is to increase the potassium level on the fertilizer bag to about the same as the nitrogen to increase tolerance to the cold weather.

Q: Is blood meal better for roses than commercial fertilizers?

A: Any form of fertilizer available as an organic form is nearly always better for plants. What I mean by organic is that some decomposition must take place for nutrients to be released. There are farm-type fertilizers, such as urea, that are considered organic by fertilizer companies. This is not an organic fertilizer to organic gardeners. In defense of farm-type fertilizers, the plant cannot tell the difference if nitrogen or any of the other elements came from an organic source or not. To the plant, nitrogen is nitrogen. However, this is not what makes an organic fertilizer more valuable to a plant. An organic fertilizer is valuable because of all the other accessory chemicals that are released through decomposition.

These chemicals are substances such as organic acids. These organic acids aid the plant in the uptake of other nutrients like iron, manganese and zinc. The overall nutrition of the plant is improved as well as the soil. The decomposition process also helps to make our desert soils more acid. This is extremely important if we are planting nondesert plants in our yard such as Indian hawthorn, photinia and other plants brought into the desert from coastal California. The major reason organic fertilizers have not been used more by gardeners is because farm-type fertilizers are cheaper, easy to use. The reasoning is that if a farmer does it this way it must be the right way.

Farmers choose certain ways primarily for economic reasons, not necessarily because it's the best way. In the past, farmers claimed that they could not afford to use organic fertilizers due to cost. This has been changing in the last 20 years.

Bob Morris is a horticulture specialist with the University of Nevada Cooperative Extension.