Summer in Oklahoma Garden Means Lots of Heat, Water and Mulch!

It feels like summer has really arrived in Oklahoma this week.  We have been very blessed so far this growing season with periodic breaks in the heat thanks to clouds, cool fronts and even some rain showers.  This was the first week of pretty much full time, unfiltered bright sun and temperatures in the mid to high nineties every day.  It looks like more of the same in the weeks ahead.  Our early spring plantings have had time to get rooted in and have grown a nice plant canopy and many of our flowering annuals and perennials have been and are blooming nicely this season.  Folks are harvesting their first big tomatoes, cantaloupes and even a few early pumpkins.  This summer weather is a real test for many of our plants as they deal with the extreme heat and dehydration.  Just like we humans need to drink more water and stay hydrated in the heat, so do our plants.  Deeper rooted and more established plants like trees, shrubs and many perennials and native plants can handle the heat and water stress better as they have a larger and deeper root system that can draw in water from deeper in the ground and using a bigger network of roots as “soda straws”.

Annuals and newer plantings that have shallow roots or don’t have as well established of a root system will show the stress of the heat and dry conditions quicker and more often.  We can grow lots of types of plants if we are faithful to take care of their watering needs.  They can grow great corn not just in Iowa, but in Guymon, Oklahoma and even the Arizona desert as long as the growers are prepared to irrigate and provide adequate water to keep the corn from too much stress.  Many plants will tolerate the high light and intense heat as long as they receive adequate water at the right times and don’t become too stressed.  Some plants will visibly wilt, some turn grayish green instead of bright or dark green, and most all will begin to yellow and drop leaves so they have less plant to support if they are under too much heat or drought stress.  Plants under stress become much more vulnerable to pest problems, like bagworms on needle evergreens, red spider mite on tomatoes and marigolds, webworms on pecans, walnuts and other trees.  As soon as you notice these pest problems, get them identified and decide on a course of action.

Help keep your plants summer strong by mulching the soil surface around them 2” or more deep with a good bark or hull mulch.  Water deeply and regularly between rains using drip irrigation, soaker hoses, sprinklers or your water hose.  Every time your plants go to the wilted stage or come under heavy heat or drought stress it saps some of their energy and momentum and acts like a growth regulator.  You surely don’t want to overwater your plants but you don’t want to get them “wilted” dry either.  Some good gardener judgment is involved to know your soil type and water accordingly.   Sandy, well drained soil will dry out more often while clay, tight soils will dry out less often.  One key reason to add sphagnum peat and organic matter to our garden soils over time is that soils with more organic matter will hold more moisture and need less regular or extra watering.  Don’t forget that above ground hanging baskets and container plantings will dry out quicker and will need to be watered more often.

You can still plant in this heat as long as you will be faithful in watering these new plantings.  Like the stories of the cobbler’s kids being the last to get shod we horticulturists are often the last to get our own gardens planted because of being so busy serving others in spring.  Dona and I have done most of our plantings the last two weeks and there may be a little sunburn and extra “heat wilting” for the first few days or even weeks as they adjust to their new home but with adequate water they will adapt well and look great as the season progresses.  You can still plant as long as you will water and mulch!


Midway Point of Our Gardening Calendar!

We have arrived at the midway point of the 2017 calendar and are a little over a third of the way through this growing season.  Time marches on without pause and we are at a point in the growing season where many of our spring plantings are really starting to make a show.  The summer flowering shrubs are producing waves of colorful flowers.  The vitex or butterfly bush is covered with blue flowers.  The crapemyrtles are impressive this year dressed in all tones of pink and red, purple and white flowers.  Crapemyrtles not only produce one wave of flowers but often will bloom repeatedly throughout the hot summer months they love into early fall.  They are available in dwarf varieties that only grow a few feet tall to varieties that make large shrubs or even small trees at 20’ tall or more.  There is a lot of active breeding and variety selection growing on now for new crapemyrtles.  The most prolific breeders are the National Arboretum in Washington D. C. and Lacebark Publications operated by Dr. Carl Whitcomb, right here in Oklahoma at Stillwater.  Gardeners all over the south half of the country are growing new varieties bred and grown right here in Oklahoma.

Other summer flowers putting on a show include the lovely cannas, started from a tuber or purchased as a plant.  These large leaf plants produce impressive flower stalks of red, pink, yellow or orange cannas with either green or reddish foliage.  Many of our perennials bloom now as we enjoy our longest days of the year including white Shasta daisies, Echinacea, gazania, and the impressive Rudbeckia also known as Gloriosa daisy or coneflowers with their exciting yellow and orange flower petals spiraling off the black or brown flower center.  Rudbeckia were first named by Linnaeus and recent breeding has produced lots of stunning choices for your summer garden.

Those of you that are vegetable gardening are now digging your early crops of potatoes and onions.  The tomato plants have really grown over the last few weeks and you should have quite a bit of fruit showing on your tomatoes and may have already had a few fruit  turn red.  Many more tomatoes should start turning red over the next week or two. Green beans and squash are producing their crops while the cantaloupe and watermelon fruit is visible under their canopy of foliage and just needs time and water to product their tender, thirst quenching melons.

Many of the annuals that love the heat are now exploding with color.  Look for lantana, penta, periwinkle, marigolds, zinnia, rose moss, sweet potato vine, copper leaf plant and many other warm blooded crops to respond well to our summer heat.  Even the plants that love the heat the most still need regular and adequate watering to perform well.  Remember your plants can’t turn on or operate the water hose yet so please remember to check your watering regularly and water and mulch your plantings to keep them healthy, happy and growing through our hot and dry summers.  You can still plant container grown annuals, perennials, vegetables, herbs, trees and shrubs as long as you will commit to provide adequate water to get them established.

We continue to be blessed with mild, even beautiful mornings and evenings so this really is a good time to get outside and smell the roses and all your other pretty and amazing flowers and vegetables.  Don’t forget to enjoy the cooling natural shade of your trees in the heat of the day.

Hot, Dry Weather quickly changes Our Garden Priorities, Water & Mulch!

Temperatures this week moved into the upper nineties and rain has about disappeared from weather forecasts as Oklahoma looks to have moved into the summer frame of mind.  Fortunately we still have pleasant nights and mornings with those temperatures still touching the lower seventies and giving our plant materials a chance to relax and de-stress during those cooler hours.

The hot, dry weather quickly changes our priorities in the Oklahoma garden.  Watering becomes the most important priority to care for our established plants, the plants we started earlier this spring and particularly any plants we plant now as the weather turns hot.  We lose moisture to dehydration as the bright sun and heat pull moisture from points of high concentration in the plant and the soil.  We lose moisture to hot, dry, blowing winds that visit us regularly in Oklahoma.  When there is no natural rain to replace this moisture, your trees, shrubs, vegetables, flowers and lawn become dependent on you to keep them in a healthy, growing condition.  Many plants will survive through the hot dry weather but make adjustments to stay alive.  As they stop growing they will wilt, get a grayish tone to their color and will shed leaves to reduce their “plant operations” to the available moisture.  Those things happen if you do not water sufficiently to keep them in a healthy vegetative state.  It causes great harm to most plants to get excessively dry or to go through extreme wet/dry cycles.  Watering needs vary a lot depending on your type of soil, amount of organic matter in the soil, whether the plants are in full sun, shade or partial sun.  Other factors are whether plants are planted alongside concrete walks or driveways, in front of concrete or metal walls, growing in a container or in a ground flowerbed, in the wide open or a wind protected microclimate.   Do you water by hand, drip or sprinkler and are the soil surfaces mulched or is there bare soil exposed to the sun’s heat and our blow dryer winds?

Giving your plants sufficient water keeps the plants in “go” mode, growing larger canopies, producing flowers, veggies, fruit and nuts.  Heat stress and drought is like throwing up a stop sign and causes the plant to reduce operations and growth to the available water.  Many plants will bounce back from one or several heat stresses or wilting but repeated stresses can kill or stunt plant development.  Pull or remove weeds that compete with your chosen plants for precious water resources, mulch the tops of your container gardens and flowers beds with two or three inches of bark or natural hull mulches and consider installing drip irrigation or using soaker hoses.  When you water, soak good so the water penetrates several inches down in your soil.  It is better to soak one to three times a week depending on your plants and soil type rather than to spray or squirt the plants every day.
Besides watering and weeding, this is the season to be alert for insect problems.  We usually see fewer fungus and diseases problems in the heat but we see an increase in insect problems as most insects lay many more eggs in hot weather and more often so populations can appear to explode.  Be on the lookout for aphids, mealy bugs, spider mites, bagworms, webworm and other unwanted insect challenges.  You can identify them using garden books, the internet or take a sample in a sealed plastic baggie or paper bag to your local garden center.  They can help you evaluate control choices whether you want to look at organic or chemical options.

The season finally slowed down a little so while many of your are digging potatoes and onions and preparing to pick your first squash, cucumbers and tomatoes we are finally getting to plant our tomatoes, peppers and lots of pretty flowers.  You other procrastinators can join us in planting now as long are you remember to water regularly to help these new plants get well established.

In the Heart of Prime Planting Season for Warm Weather Plants!

We are still in the heart of the prime planting season for all the warm weather annuals and color plants as well as perennials, shrubs and trees.  We have been blessed with regular rains and moderate temperatures so we have a wonderful extended planting season this year.  This is a great time of year to visit your local nurseries and garden centers to see the full selection of plant material that can be grown here in Oklahoma.  We have a huge palette of plants that can be grown in Oklahoma although we have to pay attention to get the right plants in the right locations.  The main keys to gardening success in Oklahoma usually come down to soil preparation, getting the sun/shade light (heat) levels correct when we pick plant location and watering.  Since we are a true four season state we get to see plants like pansies and kale that do well, even in full sun, in the cool parts of the year but succumb to the heat as summer temperatures and longer days confront us.  This time of year is a good indication as the pansies that survived the winter and looked great this spring begin to melt or wilt away in the increasing heat.  Other crops like sweet potatoes, caladiums, periwinkle or vinca, okra, melons, hibiscus and many other tropical plants love the heat, as long as they get adequate water and will grow and flower or fruit best as they thrive in the heat of an Oklahoma summer.

This is a good time to plant while selections are still good and the summer heat is not yet overwhelming so that new plantings have a good chance to get rooted in before the extreme heat.  You can plant container grown and balled or burlapped trees and shrubs with an intact root ball ready to transplant.  You can plant virtually the full smorgasbord of color annuals and perennials to add color and life to your landscape.  You can still plant most all the warm season vegetables including tomatoes, peppers and eggplant and we are nearing the end of the planting window to sow seed or plant transplants of summer and winter squash, cantaloupe, sweet potatoes and watermelons.  You can sow seed of Bermuda grass or install sprigs or sod if you are typing to establish a summer lawn in a sunny location.

This is the season for container gardens if you want to add color to a patio, front porch, balcony or other area for a summer party, family get together or just for your own enjoyment.  Remember above ground containers will need more water and more often than ground beds and the smaller the container the more often it will dry out and need water while larger containers with more soil media will need less attention.  You can grow ornamentals or vegetables in your container gardens.  There are literally hundreds of choices in the containers you select and the plants to go in them to allow you to express your artistic or design personality.

All new plantings will require more water than established plantings as they grow their root systems and get settled into their new environment.  You can reduce your watering needs and the urgency of watering by mulching your new and existing plantings with a surface mulch of shredded bark or hulls.  This garden practice of mulching will often reduce watering needs by up to half while cooling the soil and reducing weed pressure.

Not only our desired plants are growing good as the temperatures warm up but also the insect and disease activity picks up as the temperatures rise. Our disease problems are worse after rains or when we have extended dark, cloudy weather or very high humidity.  The insect pressure is largely driven by heat.  If you face an insect or disease you don’t recognize or know how to respond, put a sample in a zip lock bag and take it to your local garden center, nursery or the nearest OSU County Extension Office to Identify and suggest a solution.

There was a great Garden Festival at the Myriad Gardens last Saturday and today the Oklahoma City Council of Garden Clubs is hosting a plant sale and garden festival at the newly remodeled Garden Exposition Building in Will Rogers Park if you want to go exploring for plants today.

Get busy planting and enjoy this magnificent planting season!

World Naked Gardening Day on the First Saturday of May is the Season to Plant Away!

Today is the well publicized World Naked Gardening Day which is the first Saturday of May, but I suspect most Oklahoman’s will participate inside their safer protective clothes.  It is a good thing World Naked Gardening Day wasn’t last weekend when it felt more like winter then spring in Oklahoma.  The weather forecast looks like all the snow and cold is now in our rear view mirror and we really can concentrate on spring planting.

May is the season when we can plant most everything and have a good chance of gardening success.  If you want to vegetable garden, whether in traditional garden rows or in patio pots or the fun new fabric grow bags this is the time to plant your tomatoes, peppers, and eggplant.  There are many other veggies you can grow from seed including warm season crops like okra, cantaloupe, cucumber, pumpkins, black-eyed cow peas, summer squash, winter squash and watermelons.  The night temperatures look like they will now be 50 degrees or higher so you can plant sweet potatoes slips that will allow you to dig your own fresh sweet potatoes later this year.

Colorful annuals and perennials provide a lot of the spark or pizzazz for our yards and patios.  There are literally hundreds, even thousands of choices of the plants you can use to add color and excitement to your home.  You need to consider light levels like sun or shade, soil type and drainage as well as your watering habits to help select the right plants to fit each area of your yard.   You also need to think about the height the plants will grow, the size and shape of the plants and the colors of their flowers to get the right fit for your landscape.

Almost all plants do best when you have prepared the soil right with the addition of good organic matter like sphagnum peat, composted bark, cotton burrs or other humus to help provide a well drained home for your plant roots.  These composted materials also help hold and release moisture in the soil and tend to help acidify our alkaline soils.

Shade and part shade areas can be dressed up with plantings of impatiens, caladiums, begonias, salvia, coleus and many wonderful perennials.  The smorgasbord is full of great choices for sunny garden color in Oklahoma including lantana, petunias, crotons, plumbago, petunias, ornamental sweet potato, zinnia, marigolds, periwinkle, sun coleus, ornamental grasses and pentas.

This is also a good time to plant container grown shrubs and trees.  Many folks had a lot of tree damage last weekend and this may be a good time to replace those wind damaged Bradford Pears or other fast growing, soft wooded trees.  We are blessed to have lots of choices in the trees that will grow across our state but you really do need to think about whether you want a tree in twelve to twenty years that will grow to fifteen feet, twenty-five feet, thirty-five feet tall or even larger as you select the tree for your available space.  There are trees that provide shade, others that provide fall color, some that produce fruit or nuts, others for spring flowers.  Some trees will cover multiple uses in addition to their aesthetic impact and the amazing job they do in cleaning your air and providing cooling for your home and property.  Shrubs make a big impact around your home or other buildings as foundation plantings and as living fences or screens.

Decide what kind of landscaping or gardening you need or want to do this season and get busy planting to take advantage of the full 2017 gardening season.  Don’t forget Mothers Day is one week away and plants make a great gift to celebrate and honor the special women and mothers in your life.   May is the season to plant away!

Celebrate Oklahoma Land Run and Plant Away!

What better way to celebrate the Oklahoma Land Run anniversary today than by driving your spade in the ground and planting new trees and shrubs to stake your modern day claim to your yard.  On this day in 1889 our ancestors were lining up to rush into these new territories to stake out their new homes and farms.  A lot has happened in the last one hundred and twenty-eight years as most of those lands have changed hands several times and had real homes replace sod houses and barns.  Those one hundred twenty-eight years have seen wells drilled, water lines and storm sewers installed, roads and highways created and electricity installed across these plains.  Our Oklahoma forefathers were mainly trying to grow enough vegetables, fruit and grains to feed their families and their livestock as they attempted to survive in this new frontier.  It was a bonus when they got to plant roses, iris or other pretty ornamental flowers to brighten their harsh life as homesteaders.  We have the luxury of being able to choose what type of landscape and gardening we want to do.  We are not gardening for survival but for enjoyment, relaxation, beauty and to supplement our food supply.

We are likely past the last freeze or frost of the winter and are into the main spring planting season.  This is the sweet spot between winter and the heat of Oklahoma summers where we can plant most anything and have a fairly high chance of gardening success. Crops planted now and watered correctly have a good chance to get rooted in and established in their new garden home before confronting the intense heat trials of summer.  This is the season where you can “plant away” on most everything from grass seed, sprigs or sod for new lawn areas to container grown fruit or ornamental trees for shade and nutrition.  You can also plant container grown shrubs to create hedges and for foundation plantings around your home or other buildings.  This is a great time to plant perennials to provide seasonal color and to come back year after year to anchor your gardening efforts.  Some of those trees, shrubs and perennials across our state date back to those the pioneers brought in on their covered wagons during the land run.  We still see heirloom roses at old homesteads and at early day cemeteries as well as lilacs, iris and day-lilies that were first planted soon after the Land Run.

The most popular plants to add to your garden during this spring planting season are the annual vegetables and color annuals.   There are many warm season vegetables you can start from seed now to enjoy throughout the growing season but the most widely grown Oklahoma vegetables are tomatoes, peppers and eggplant which are usually grown from transplants or small plants you can buy at your local nursery.  These can be grown in traditional vegetable gardens, mixed in with flower plantings in flower beds or grown in raised beds, or even fabric bags or decorative containers on your patio or even on apartment balconies.  There are hundreds of varieties of tomatoes from small cherry or plum sized tomatoes to large slicing tomatoes in traditional red, pink, yellow or purple skinned selections.  Peppers vary from sweet bell peppers to sweet banana peppers and hundreds of different intensities of hot peppers.  Eggplant is often used as a meat substitute and is available in several varieties producing different sizes and colors of fruit.

Flowering annuals add the color or pizzazz to our yards and landscape and the choices expand every year as more plants are introduced and as plant collecting and breeding progresses.  You can plant for mass color impact like a bed full of begonias, impatiens, penta, petunia, periwinkle or vinca, marigolds, zinnias or many other choices.  You can plant to support pollinators, to attract butterflies, to provide touch or scent gardens.  There are so many plant choices you can be an artist and show your creative side based on the plants and colors you select.  Make sure you pay attention to your soil type, drainage conditions and amount of sun or shade available as you work with your local garden center or nurseryman to make your plant selections.

There are a few really hot blooded crops like okra, sweet potatoes, periwinkle and caladiums that will do better if you wait another week or two to plant when the night low temperatures are consistently above fifty degrees.  Except for those few crops “plant away” and get ready to enjoy and be a part of a great growing season.


We were really dry, so dry that western Oklahoma lost tens of thousands of acres to wild fires.  We have now been blessed with some nice soaking rains across most all of Oklahoma which really help get our trees, shrubs, lawns, vegetable and flower gardens off to a great spring start.  Water is one of the most critical ingredients to support plant growth and nothing beats great slow soaking rains to motivate our plants to produce a flush of spring growth.  This is an exciting and tricky time for Oklahoma gardeners.  We have enjoyed beautiful spring like weather for several weeks which adds to our spring fever and calls us to plant!  Our instincts tell us that the earlier we can plant without getting a freeze the earlier we get tomatoes, peppers, flowers or other crops.  Early planting also get us a longer growing season to enjoy annuals before we have to confront fall freezes.  Early plantings allow more plant growth while we have pleasant spring weather and before we confront the intense heat of our Oklahoma summers.  The better established and rooted in our plants are before the stress of summer the better they can handle that heat and drought.  The challenge for gardeners is that threat of a late cold front that can kill or damage these early plantings.  Our last average frost in central Oklahoma is around April 10 and we currently show nothing below 40 degrees on the ten day forecast so it looks all clear to plant most everything.  Bear in mind we have had a killing freeze in just the last few years as late as May 3rd so you still need to be weather observant and ready to protect these early season plantings if we do get a late surprise cold front.  Based on the current weather reports it appears like you are good to plant most everything but the hot blooded tropical plants like sweet potatoes, periwinkle, okra and caladiums that do best planted after night temperatures are consistently above fifty degrees.  These hot blooded tropical’s will be lethargic and usually just sit there when planted before May 1st.

This is a great season to plant new container grown trees and shrubs.  They will benefit from spring rains and the natural urge to root out at this time of year.  Remember that new trees and shrubs will require an extra commitment to water this summer and even the next couple of years until they are rooted in more deeply.

Few gardening experiences are as much fun as picking your own fresh vegetables to wash and eat fresh or to use in your own salads and cooking.  Plant tomatoes, peppers, and eggplant transplants now to start picking locally grown produce in late May and June.  Tomatoes and peppers are still the most popular vegetables to plant and harvest yourself.   There are hundreds of varieties of each.  There are giant slicing tomatoes, cherry or pear tomatoes, red tomatoes, yellow tomatoes, and heirloom tomatoes.  Plant varieties you have had good success with and try out a new color, shape or variety to add some excitement to your vegetable gardening.   It is best to select a tomato variety that is VFN for resistance to verticillium, fusarium and nematodes.  Peppers are available in hundreds of varieties from sweet bell peppers in green, red, purple or new multicolored varieties to sweet banana peppers or hot peppers of varying intensity.  Hot peppers are rated in scoville units and although I have a limited tolerance for the hot pepper varieties many folks love them hot, the hotter the better.  Tomatoes, peppers and other vegetables can do well in flower beds, often even better in raised beds that may have better drainage and better soil.  You can also raise tomatoes, peppers and other veggies in decorative containers or other styles of container gardens on an apartment balcony or your home patio.

Plant now to get your plants off to a great spring start and to get a full growing season.  Be weather observant so you can protect your plants if we are challenged with a late cold front and to water your plants when dry.