Hoop Houses Extend Growing Season

Get head start on spring growing with hoop houses

Bill Sevier Ask a Master Gardener

Saturday, December 31, 2016

Q: I am interested in a hoop house. How do I get started? J.M., Tulsa

A: First, go to the OSU Tulsa Master Gardener website, tulsamastergardeners.org, and look under “Tips and Techniques.” Master Gardener Gary Sanders has written instructions for an easily constructed small hoop house.

Hoop houses, also called high tunnels, have many different designs and uses; some are built on a large scale for commercial growers of vegetables and cut flowers; much smaller ones are used by homeowners. OSU has a fact sheet about high tunnels, HLA-6720, “High Tunnels,” which has a great deal of practical information about construction and management.

Hoop houses basically consist of bowed hoops, or arches, formed from various materials such as PVC or other types of bendable plastic pipe. The ends of the hoop are fixed either to a raised bed frame or anchored in the ground over a bed. The house is then covered with translucent plastic greenhouse film secured to the hoops and garden bed. The ends and sides are generally created in such a way that they may be opened up for ventilation when needed.

Hoop houses should be located in full sun and close to a water source. The location should have some wind protection; the plastic covers are susceptible to wind damage. Drip irrigation, which can easily and cheaply be installed, is ideal for this situation. The planting area is best if it is a raised bed, either a simple mounded bed of soil or one constructed of a wood frame. In any case, it should have good soil, high in organic material that drains well.

Hoop houses can give you a head start in spring for your cool-season vegetables or for growing sprouts. In fall, the same cool-season vegetables will produce deeply into winter. Some of the cool-season vegetables that may be grown include cabbage, cauliflower, collards, kale, broccoli, Swiss chard, lettuce, onion, radish, spinach and turnip.

A hoop house will also extend the growing season of warm-season vegetables like tomatoes.

It is estimated that a hoop house extends the frost-free growing season by as much as two months. If you place a second layer of plastic or a row cover fabric directly over the plants, the growing season for some vegetables can be extended throughout the winter.

Hoop houses do require regular care. Heat is collected from the sun shining through the plastic, and when too high, the ends of the house must be opened to allow the wind to cool the plants. In summer, when the temperature outside is above 90 degrees, a shade cloth should be placed over the house for additional cooling.

Consider building a hoop house, it is an easily constructed and useful project which is surprisingly productive.

Garden tips

• Any green weed in dormant (brown) Bermuda lawns may now be sprayed with glyphosate, found in Roundup and many others. This will kill anything green but will not hurt the Bermuda. Glyphosate cannot be used on dormant zoysia grass or tall fescue lawns at any time.

• Control overwintering insects on deciduous trees or shrubs with horticultural oil sprays in dormant concentrations; applied when the temperature is above 40 degrees in late fall and winter. Do not use “dormant” oils on evergreens.

• Inspect your irrigation system and replace worn or broken parts.

• Shelled or unshelled pecans should be stored in an airtight plastic bag or container in the freezer. Care should be taken that they are dried beforehand.

Options for Disposal of Christmas Trees

Repurposing Christmas trees benefits environment

Brian Jervis: Ask a Master Gardener

Saturday, December 24, 2016

Q: Can my Christmas tree be placed curbside with my trash for city pick-up? R.M., Tulsa

A: Yes, the city of Tulsa will take your Christmas tree, along with your trash on your regular pick-up day. They do recommend the tree be 6 feet in length or less and suggest cutting it up, if your tree is longer.

However, there are several other options for your tree that are more environmentally friendly than sending them to the trash to be burned.

They may be used for a bird shelter, mulch for your garden beds, submerged in a fishing hole, shredded, or taken to the Tulsa Green Waste site.

Trees may be shredded into mulch in a couple of ways. All of these methods involve removing all tinsel and other decorations beforehand.

First, Southwood Landscape and Garden Center, 9025 S. Lewis Ave., and Owasso Tree and Berry Farm will take live-cut trees and recycle them for either mulch or fish shelters. You need not have bought your tree from these businesses for them to accept it.

Another way to recycle your tree, if you are able, is to take it to the city of Tulsa’s Green Waste Site. It is located at 2100 N. 145th East Ave. and is open seven days a week from 7:30 a.m. to 5 p.m., closing only on city holidays. The service is free with proof of Tulsa residency. At the green waste site, you may also obtain all of the free woodchip mulch you may need. In addition, free firewood is available.

Birds need sanctuaries from the cold and predators in winter. Christmas trees near a feeder offer a great refuge until spring and trees begin leafing out. You can also help them out by placing treats such as peanut butter and suet on the limbs for a high energy source. This would be an interesting project for a child.

Recycled Christmas trees also work well submerged into a lake or pond as a fish shelter. These piles of trees are productive for certain types of fish. This is especially true for attracting crappie.

The smaller limbs and fronds can be removed and be placed in the garden bed as a green mulch. After removing the limbs, the remaining trunk can be used as a stake in the garden. The limbs used as mulch will decay over time, and you will reap not only the benefits of a mulch, but also the nutrients they release onto the soil.

These limbs also may be added to your compost pile as a source of green material to help balance the brown material such as leaves. Green (nitrogen source) and brown (carbon source) are needed by the microbes that break down the material. For those new to composting, OSU has an informative fact sheet, HLA-6448, “Backyard Composting in Oklahoma,” available with an online search or from the OSU Tulsa Master Gardeners website.

Garden tips

§  Don’t forget to keep the compost pile watered. The decay process to produce garden-friendly compost continues in winter if the pile is large enough and kept watered and turned.

§  Cover strawberry plants with a mulch about 3-4 inches thick if plants are prone to winter injury.

§  Wait to prune fruit trees until late February or March.

§  Wilting and drooping of leaves on evergreen trees and shrubs is common when the temperatures drop low. This is a way pla

Be Careful When Using Fireplace Ashes in the Garden

Fireplace ashes can harm gardens

Bill Sevier: Ask a Master Gardener

Saturday, December 17, 2016

Q: Is it OK to spread my fireplace ashes over my vegetable garden every winter? N.G., Sand Springs.

A: The best answer is “probably not.” Ashes from burning various types of wood have a unique chemistry, which might be useful in some situations but are not recommended for vegetable and ornamental gardens or for lawns, with few exceptions.

The problem with ashes is three-fold, two of them significant. One is that the pH is high. The pH is a measurement of level of acidity on a scale of 0 to 14, with 7 being neutral, 0 very acid and 14 extremely alkaline. Examples of the pH of some items are: Battery acid pH of 0, lemon juice pH of 2, pure distilled water pH of 7, baking soda pH of 9 and household bleach has a pH of 12-13.

The pH range of fireplace ashes has an average value of 11.6, right up there with household bleach. Added to soil, it removes acid, driving the pH value up and out of the range of acidity that most plants prefer.

Most vegetables and lawn grass perform best in slightly acidic soil of an average pH range of 5.8 to 6.5. Many shrubs need even lower pH values. Azaleas, blueberries and gardenias need an acidic pH of 5 to 5.5. Other acid-loving shrubs include most conifers, camellias and hollies.

When the soil is out of the pH range needed by a particular plant, it cannot absorb nutrients, such as iron. This is the reason for yellow leaves on many azaleas growing in soil that has become too alkaline, producing yellow leaves that have a distinctive pattern called iron chlorosis.

Another downside to using fireplace ashes is the amount of salt. Excess salt in soil will predictably kill plant roots. An example of this is seen with the use of salt on roadways in winter with subsequent death of roadside plants the following spring. Once the salt is in the soil, it may take a long time for correction to occur.

The last concern about fireplace ashes is the amount of potassium. There is about 6 percent potassium in ashes, and they will add this nutrient to soils, which if deficient, could be helpful. However, the results of soil tests of Tulsa-area gardens by OSU show that in previously fertilized soils, the majority have adequate or excessive potassium.

OSU has a fact sheet “Fireplaces Ashes for Lawn and Garden Use,” which offers a good summary of chemical content of various ashes from burning different hardwoods. The fact sheet recommends that if ash is used, one should use no more than 10 gallons per 1,000 square feet in sandy soils and 20 gallons for the same area in other soil types. The key take-home fact from this document is that if you apply ashes to your soil as outlined above, you should do so no more often than once every 10 years.

Garden tips

§  All birds need and appreciate clean feeders and unfrozen water on cold days. Place feeders close to protective shelter, if possible.

§  Select a freshly cut Christmas tree. Make a new cut prior to placing in tree stand. Add water daily.

§  Light prunings of evergreens can be used for holiday decorations. Be careful with sap that can mar surfaces.

§  With the warmer weather, newly seeded fescue will continue to grow roots and make energy if you keep them free of leaves.

Planning a Vegetable Garden

A Vegetable Garden Requires Planning

Brian Jervis: Ask a Master Gardener

Saturday, December 10, 2016

Q:I am thinking of planting a vegetable garden this spring. I am not sure how to get started, can you help? T.M., Sand Springs

A:Vegetable gardens are enjoyable and productive for most gardeners, but the key to success is in the planning. Planning for both the proper location, choices of vegetables and times to plant.

The OSU Tulsa Master Gardener’s web site has good information to help you. Go to the vegetable section and review OSU fact sheet, # 6004, “Oklahoma Garden Planning Guide”. This fact sheet has the how, when and where of starting a vegetable garden. Most all of the vegetables grown in Oklahoma are listed with dates as to when they should be planted, whether to use seeds or transplants and days to harvest. Other fact sheets in this section list the varieties of vegetables which grow best in our area.

Location is key. Most vegetables grow best in full sun although some of the cool season vegetables (cabbages, lettuce and others) will tolerate some shade. A north-south orientation of the rows will maximize sun exposure.

It is best to have a garden near you and near a source of water. The closer it is located, the more likely you will visit the garden and deal with problems early.

If you have good soil you are fortunate. When soils have too much sand or clay there are two ways to improve them. One is to till in large amounts of fully composted organic material. This will help sandy soils retain water and nutrients and aid heavy clays to more easily drain and to allow root penetration.

The other option for problematic soils is to plant in raised beds. With raised beds you should import good soil which bypasses the problem with native soils. Raised beds may simply be mounds of good soil without a containing structure, or better, construct a container out of wood, stone or other material.

A related option to raised beds is to plant in containers. It is surprising how productive a pot on the patio can be. Many vegetables grow well with this method. In addition, they may be moved about to deal with sun and shade.

It is best to perform a soil test at the start to decide what nutrients are needed when selecting fertilizers. Helpful information about how to fertilize vegetable gardens may be found on the Master Gardener web site.

Most all vegetables will also need mulching to conserve moisture, prevent weeds and help to moderate the soil temperature. Any mulch is OK, there is no “best” mulch.

Remember, all gardens will have some insect or disease issues in the course of the growing season. Regular inspection will identify problems early so they may be dealt with more easily. The OSU Master Gardeners can help with all of these problems by calling our helpline at 918-746-3701, M-F, 9am to 4pm; or come by the office at 4116 E. 16^th street, gate # 6 into the Tulsa Fair Grounds.

Garden Tips

Firewood information may be found in OSU Fact Sheet NREM-9440. This fact sheet outlines which types of wood burn best and also describes how to obtain and measure wood. Tips on how to cut and split wood safely are also described.

One thing you should not do, when obtaining firewood, is to transport it any significant distance. Because of the high incidence of many types of invasive insects in firewood, such as the Emerald Ash Borer, many states ban all imported firewood. A good rule of thumb is to not go over 50 miles to obtain wood; 10 miles is even better.

Selecting and Caring for a Christmas Tree

Choosing the perfect Christmas tree

Bill Sevier: Ask a Master Gardener

Saturday, December 3, 2016

Q: I am going to get either a live-cut Christmas tree or a live tree with roots to plant in my yard later. Which would be best? S.J., Tulsa

A: It seems that more and more people are opting for artificial Christmas trees, and they certainly have advantages in terms of cost savings. Storage, assembling and disassembling, are downsides.

Many feel that having a live tree is more in keeping with the Christmas spirit, this is especially true for older people for whom a live tree was the only option in their youth.

Live trees may come with their roots in pots or balled and burlapped to be planted later, or freshly cut, to be disposed of after Christmas.

OSU suggests that a live tree purchased for later planting be kept in an unheated and shaded area until brought inside. They should be watered regularly and planted soon after the holiday. It is best to minimize indoor time to a week.

Live-cut trees may be bought from a local vendor or you may go to one of about 15 Christmas tree farms, mostly in northeast Oklahoma, and cut your own. Look for the Oklahoma Christmas Tree Association website for details.

Many of the precut trees in local markets were shipped in from the northwest. They may be drying after having been cut for a few weeks. Dry trees lose needles and are fire hazards.

To help people pick out a fresh and good quality live-cut tree, OSU has published a list of recommendations to consider in the selection process, a summary of which is below:

• Tug the needles and bounce the butt on the ground. If green needles fall, consider another tree.

• Look for fresh green color. Some trees are sprayed with a blue-green dye to cover brown needles. Break some needles, they should be flexible and moist.

• Buy early before the desirable trees are sold.

• Fir and pine trees hold needles better than spruce trees.

• Be sure limbs are stout enough and located in such a way not only to produce a nice shape, but also to be able to support your decorations.

• Ask the dealer if the trees were locally grown or imported. Local trees are more likely to be fresh.

After selecting your live-cut tree, OSU has some suggestions for care to keep it fresh through the holidays:

• After purchase, cut an inch off the butt and immediately immerse it in plain water. No need for any additives to the water.

• Keep the tree in a cool shady area in water if there is a delay in bringing it indoors.

• Trees need a sturdy stand with lots of water; a tree may absorb a quart of water per day, so keep the reservoir full.

• Keep the tree away from heat sources such as fireplaces and air ducts. Never have an open flame near a tree.

If you follow these sensible recommendations, your tree should be safe and easily last for a few weeks, bringing a delightful addition to the holiday season.

Garden tips

• Proper care will extend the life of Poinsettias through the holiday season and beyond. Keep in the brightest light possible and away from cold windows and heating vents. They prefer a room temperature of 65-75 degrees. They will die or perform poorly with too much or too little water. When the top inch or so of the potting soil is dry, add lukewarm water until it emerges from the bottom of the pot. Discard this water. There is no need for fertilizer.

• If your roses have not been mulched, do so now. This is a good place to use those fall leaves that have been shredded with a mulching mower. Mulch not only will prevent cold damage to those susceptible plants but will keep soils from warming on warm winter days, breaking dormancy.