When does “full sun” in the plant world actually mean full sun? If you live in a place that gets very, very hot for a long time.
When we go to the garden store, our attention is drawn to an interesting species that is new to us, and we often look for small plastic picks that can stick in pots, or if it’s a packet of seeds we’re interested in, We are flipping it to learn more.
We’re looking for the strain’s biography, which tells us what does full sunlight mean? How to define full sun for gardening, how much water it needs, and how much sunlight it should get.
For those of us in the southern part of the country, that’s the crux. For example, in much of Texas, the deserts of the Southwest, or other hot and sunny parts of the United States, many species that say the plant can tolerate a lot of sunlight will simply burn.
During the summer months, these regions experience more than 12 hours of scorching sun and high temperatures every day. It is indeed a hardy plant that will tolerate this light and still look great.
What does “full sun” actually mean to us in the South and Southwest? How can we enjoy a beautiful garden without risking losing everything in the July and August heat?
Those of us in zone 8a and higher need to be mindful of how much sunlight we give our plants – although some well-watered areas may have better luck.
We consulted with experts in several states. Generally speaking, their recommendations fall into two broad categories. Let’s see what they have to say.
What Does Full Sunlight Mean?
It’s critical to measure your garden’s insolation before you start. For example, you cannot plant grass in a forest clearing or powerline easement because the surrounding tall trees block the sun for most of the day.
The definitions of the various solarization terms you might read or find on plant labels are a bit vague. “Full sun” definitely means at least six hours a day, but some plants like vegetables do need eight to ten hours a day.
“Partial sun” or “partial shade” means that plants need 3-6 hours of direct sunlight per day. These terms are sometimes used interchangeably. However, having shade in the morning is not the same as having shade in the afternoon sun.
“Partial sun” usually means that the plant needs more sun and is more heat tolerant. “Penumulus shade” refers to protecting plants from the sun in the afternoon.
Of course, “shadow” doesn’t mean pitch black. More plants can tolerate dappled shade than can live in really deep shade.
Regardless of a plant’s label, how much sunlight it needs or can tolerate depends on the intensity of sunlight and the amount of water.
If you methodically plan to bask in different parts of your yard, you may find yourself in for a few surprises. The midday heat can really provide shade for the rest of the day. Dappled sunlight in April can provide complete shade in July, when the shrub needs light to produce next year’s flowers. So make a chart right after the tree sprouts and watch it every hour.
How To Define Full Sun For Gardening
Most gardeners know that the amount of sunlight that plants receive can affect their growth. This makes studying sun patterns in a garden an important part of garden planning, especially when it comes to full sun landscaping.
Each of our experts said that choosing a location for your plant is critical.
“‘Full sun’ means 6-8 hours of sunlight,” said Ron Bowen, master gardener coordinator for the University of Arizona Cooperative Extension. “And plants generally prefer morning sunlight.”
For species that may not tolerate hours of brutal sun exposure, Bowen recommends placing them where they receive morning sun and afternoon shade.
Angela O’Callaghan, a University of Nevada Cooperative Extension agent with a doctorate in horticulture, agrees with Bowen.
Her advice to gardeners in Clark County, where Las Vegas is located, is to pay attention to directional sunlight. “If you’re growing any flowers or fruits, those plants need eight hours of sunlight, but put them in a place with bright light from 6 a.m. to 2 p.m.,” she says. “For these people, facing west may not be the best idea.”
Bowen added that some commercial growers have started including heat tolerance information on their labels. “These labels have only been around for a few years, mostly in the South,” he said, adding that it would be wise to look at the guides for more information on the climatic conditions that specific plants can tolerate.
“Hopefully more growers will adopt heat-resistant labels soon,” Bowen added.
>>> See more: using pesticides safely
Another common theme we hear from experts is the importance of choosing species and cultivars for your garden.
“You can grow just about anything if you’re willing to put in too much time and resources,” O’Callaghan said. “But does it really make sense?”
If It’s Not Meant to Be, It’s Not Meant to Be
Fascinated by the legendary beauty of rhododendrons, and perhaps remembering the enchanting scent of visiting grandma’s house as a child, the neighbors across the street insisted on planting rhododendrons.
In Austin’s notorious alkaline dirt.
They ship acidic soil, add thick mulch, water obsessively, and even get misted. They lovingly tend to nearby trees in the hope that they will provide the shade and cooling the dazzling shrub needs.
All in all, they did their best to give Rhododendron a beautiful and loving home.
Before summer becomes a memory, however, once-beautiful rhododendron bushes are already on the compost pile, replaced by more boring but very Austin-resistant sage bushes.
Morality? Mother Nature took it all out, letting Plant A grow where it made sense to Plant A, and so on. It probably doesn’t make sense when people try to sabotage their carefully crafted plans.
Trying to force Plant B to grow in Plant A’s territory is just a waste of resources and can lead to endless frustration!
Read the thought-provoking book The Humane Gardener for another reason to follow Mother Nature’s blueprint.
Ever heard of Laredo, Texas? It’s hot here. The town near the Mexican border could hit triple digits by the end of April.
Martha Ramirez, a consultant for Weber County, the county seat of Laredo, emphasized the importance of choosing local varieties. “We encourage our residents to consult our list of native and adapted plants,” she said. “We’ve struggled to identify native plants or plants that have proven themselves in our growing conditions.”
O’Callaghan and Bowen both agree. “Check with your local university office. They usually have good publications in their field,” Bowen said. He says to learn and become an informed plant buyer.
O’Callaghan also warns against trusting the information you get at garden centres, especially chain stores or major department stores. “You can’t believe everything you hear,” she said. Employees in these places work hard but often learn on the job and don’t have as much information as they can find by looking at good online resources, she added.
O’Callaghan also agrees that plant seekers should do their research before entering a nursery. “You have to know your garden,” she said. “Know where your bare patches are and know ahead of time which plant species will tolerate your garden conditions.”
Buy supplements for your garden from a locally owned gardening store, or if you go to a major department store or chain, keep a list of native and adapted plants with you so you know what works and what doesn’t in your area.
When shopping, you should also consider where certain stock specimens were raised before making it to your local store. For example, plants that thrive in upstate New York or Minnesota may not perform well in Phoenix.
When in Rome…
Now that you may know more about choosing and placing sun-loving plants for your southern garden, it may be time to look for specific species and varieties that can withstand the heat.
Make a list and check carefully. Head to the garden store with your newfound knowledge and maybe, just maybe, instead of a brown cane, you’ll see fascinating flowering greens in July.
Just choose the right plants and place them in the right places. Of course also know your climate.
As Las Vegas’ O’Callaghan puts it, “We’ve got a lot of sunshine…it’s not the same as Maine’s!”
Southern gardeners, Answer The Question loves to hear about your “full of sunshine” experiences. How many plants have you accidentally roasted? Do you trust the sunscreen recommendations of botanical labels?