Ask the determined gardener

By Freddy Hill

Oklahoma County Master Gardener

Can you list plants for a Xeriscape garden?

Xeric or dry climate gardens are a coordinated effort involving soil quality, plant species and hardscape. Many of these plants do not do well in enriched soils. Dry climate areas usually have poor water retention, usually is a raised area to prevent water pooling, various sizes of sharp gravel or sand (lots of broken edges), a porous rock like expanded shale (for air pockets) and various hard rocks for support and for creating microclimates. Succulents are the first things that come to mind, but they need to be Oklahoma hardy. Allow proper growth and maintenance space around these. Many Alpine species may flourish if you provide pockets of cooler planting areas. “Rock Gardening in Oklahoma” E-965, is a great resource for plants, planting times, and tips. Dwarf conifer plants, some sedges along with some aliums, columbine, dianthus, euphorbias, blue fescue, coral bells are some examples. Many references for Xeriscape choices are available. Research the growth needs and habits of your choices. All plants need to be well established with adequate watering while establishing. Plan for open spaces in your garden to allow for navigation and upkeep for the first few years. Observe what comes back on last year’s roots (check your research notes for perennial growth pattern) and see what reseeds in place. Document all your plants the first few years. Your year-garden will amaze the neighbors.

I’m wanting to cut 1 foot off a holly hedge. Will that harm it?

The answer depends on the growth habit and age of the hedge. As a general rule, never cut more than 1/3 of the foliage off any plant. If this is a mature 4 feet or more tall, you are probably safe to do so. Try to avoid vertical sides to allow some sunlight to the entire plant (tilt sides slightly toward center). If you have achieved your final shape, look for larger branches that may outgrow the rest of the hedge space. Branch ends 5/8” to 1” or larger may judiciously cut back an additional 2 to 3 inches to maintain your shape longer. Clear debris from under the hedge to reduce the chances of disease accumulation. Nelly R. Stevens Holly is an excellent choice for a holly to trim.

Are pine needles suitable for garden mulch?

Pine mulch, needles with a few small twigs, can be used to mulch many garden areas. Pine may be slightly acidic so works well on azaleas or blueberries, but won’t have much overall effect when used strictly as mulch. The advantage is uniform size and shape, consistence in aging color, and less likelihood of containing unwanted seeds. Home and Garden Centers sometimes have this available in small bales. You may have areas you can collect your own needles at no or little charge. The appropriate mulch is beneficial to most any crop.

How do I take a soil sample and what do I do with it?

A properly collected soil sample can get you well on your way to having a great gardening year. Select a designated area you will grow a certain type of plants. Warm season or cool season turf, fruit trees, vegetable gardens or specialty crops like blueberries, each does best with a certain balance of Nitrogen Potassium and Phosphate as well as a proper pH level and organic matter in the mix. Take 12 to 15 samples throughout the area you are testing. These should include sections of soil 1 through 6 inches deep. Mix these in a plastic tub and bring a quart baggie of this mix to your County Extension Office. Let them know your target crop (you will need a complete set of samples for each various use. There is a $10 charge per sample, which will give you results and explanations for any corrections needed. Results are normally available in about 2 weeks. It may take a couple of years for your changes to take effect.