Published: September 10, 2009 02:58 pm      

Fighting an uphill battle: Proper plant selection

EDMOND — We have all heard this saying before: “I was just in the wrong place at the wrong time.” Some folks may even be unfortunate enough to know the feeling. It’s when you know that if the situation were tweaked just a bit, life would become a breeze.

Well in many cases this is exactly what a plant is trying to convey. The No. 1 factor in a plant’s success or failure is that it gets planted in the right spot. By selecting the right plant for a specific area, gardening can become a downhill slide, rather than an uphill battle. Here are some tips to consider before purchasing this fall.



Sun or Shade

The factor that seems the most obvious is sun tolerance. Not all plants can take the Oklahoma heat. If a plant is getting too many rays it can get scalded or scorched. Uniform yellowing or browning on the edges of the leaf are some typical symptoms. The leaves also may get a bleached-out appearance if they are being overexposed to the sun. Most trees will tolerate quite a bit of sun, but some of the smaller ornamental trees like the Japanese Maple, (Acer palmatum) will struggle. But, if it is provided three to four hours of morning sun and afternoon shade, it can be a beautiful addition to the landscape. When shopping, most plants will have their sun/shade preference listed. Remember that the sun is more forgiving in the morning than in the afternoon.



Cold Hardiness

According to the USDA Cold Hardiness Map, most of Oklahoma falls into the 7a–6b zones. This means that any plant with a rating of 7a or lower should survive our winters here. A higher number means that the plant is less tolerant to cold weather. It is important to look at the zone that is listed with the plant, not just the annual/perennial designation. Many people purchase a plant with the belief that it is a perennial, because the tag says so. The plant may very well be a perennial in Florida, but it will not survive our cold Oklahoma winters. It is possible to use some plants from warmer zones as perennials if extra precautions are taken. Planting on the south side of a building, in a wind-blocked area, and using mulches are all ways to help protect a plant from harsh winter exposure. These may help, but the best bet is to follow the guidelines for each plant.



Dirty Business

Before spending a large sum of money on a tree or shrub, why not spend a small sum on a soil test? A standard soil test will give the pH of the soil (acidity or alkalinity), and the levels of nitrogen, phosphorous and potassium. The test takes about two weeks and costs only $10. The best example of how these readings can affect a plant is the Pin Oak (Quercus palustris). It is a tree that prefers an acidic soil, 4.5-5. Most of the soil in central Oklahoma has a pH of 6.5 or higher. When the pH is too high, iron becomes unavailable to the plant, causing the leaves to yellow. This can make the tree more susceptible to diseases and stress, and eventually may kill the tree. The best solution is not to plant a tree in an unsuitable environment. If it is an acid-loving plant, it may not like living in this area. The Extension Office has a list of trees suitable for the area.



Plan for the future

It is important to see the big picture when buying a tree or shrub. The plant may be small initially; but if properly cared for, your new investment could grow to be a large one. So look around at your space. Try and avoid planting too close to any structure or hardscape in the area. This way the plant will have room to grow, and will not be invasive to nearby structures. Also consider how high the tree or shrub will grow. It is not wise to plant a large tree below utility lines or near the street. By planting a smaller variety, less maintenance will be needed to keep the tree from becoming a safety hazard in the future.

When a plant is provided the optimum environment it is more likely to become resistant to pest and disease problems. Many headaches easily can be avoided by making proper selection and placement decisions. Why make gardening any harder than it needs to be? For more advice on this topic, or any of your gardening questions, call the Oklahoma County Master Gardeners at 713-1125.



SAMANTHA SNYDER is a horticulture educator for the Oklahoma County OSU Cooperative Extension Service.