Episode 35: What’s Going On With My Gardenias?

About This Episode

In this week’s episode of Ask Grumpy, Steve Bender, also known as Southern Living’s Grumpy Gardener talks about common gardenia problems. Plus, Grumpy’s tipof the week to beat the Southern heat.

Question Of The Week

I live in Snyder, Texas, and have six gardenias. I've fertilized them and given extra water and soil conditioner, but most of the leaves have turned yellow and fallen off. What is wrong?

Grumpy Gardener Answer: This is a very common problem that we see with gardenias. Gardenias are like azaleas and camellias. They need acid soil. This means that the soil has to have a pH no higher than around 6.0. Unfortunately, for you, the only place in Texas that has acid soil is East Texas and Snyder is in West Central Texas. So that means you have alkaline soil. That means that the pH is probably seven or above, and what happens is that kind of soil prevents the plant from absorbing the necessary iron from the soil. As a result, you get a condition where the leaves will turn yellow with green veins and we call this chlorosis. So if you want to grow gardenias in Snyder, you have to fix the soil. And you can do this two ways:

1. You can acidify the soil by sprinkling garden sulfur or an acid fertilizer like Holly-tone around the plant and watering it in. But this is something you're going to have to keep doing year after year, it's just a temporary solution.
2. What I think would be easier for you and more successful is that you grow your gardenias in containers filled with bagged potting soil from the garden center. This way, you won't have to keep fixing the soil over and over again.
   

Tip Of The Week

How To Care For Lawn When It's Hot, Hot, Hot

It's totally miserable. And not only are you miserable when you go outside, but your lawn is miserable too because it's hot. Maybe it hasn't rained for a couple weeks. Everything is looking crispy. So when your lawn is miserable like this, why would you want to make it even more miserable? But a lot of people do. They go out there and they cut the grass during hot, dry weather. This is a really bad thing for your lawn. And some of them even take it to an extreme, they do what we call scalping. And that means you're cutting your grass basically down to the dirt. What happens when you take this too far? Two things happen immediately when you do this.

• The roots of your grass plants stop growing. So the lawn stays thin and that leaves a lot of room for weeds to come up.
• Second, you've gone from a green lawn now to one that's immediately gonna turn an ugly brown color, so you can't stand that anymore. You get out there and you got to water the heck out of it. And then you mow it and then it turns brown and you get into this cycle where you're wasting all your energy in water. Don't do that.

My advice is don't mow your lawn when it's 95 degrees and it hasn't rained, unless you have a sprinkler system that you put on every day like so many people do. I would let the lawn grow taller. Don't cut it low. The lower that you cut your grass in the summer, the more weeds you're going to have. Trust me on this. I would say for most lawn grasses, when it's in the dog days of summer, you probably should let that grass grow at least two inches tall before you cut it. And if you're growing St. Augustine grass or tall fescue, I'd let those things grow to three inches tall. The lawn will do a lot better, you won't need to use as much water to keep it green and it will thicken up a lot better than if you go out and scalp it.

About Ask Grumpy

Ask Grumpy is a podcast featuring Steve Bender, also known as Southern Living’s Grumpy Gardener. For more than 20 years, Grumpy has been sharing advice on what to grow, when to plant, and how to manage just about anything in your garden. Tune in for short episodes every Wednesday and Saturday as Grumpy answers reader questions, solves seasonal conundrums, and provides need-to-know advice for gardeners with his very Grumpy sense of humor. Be sure to follow Ask Grumpy on Apple Podcasts, Spotify, or wherever you listen so you don't miss an episode.

Editor’s Note: Please be mindful that this transcript does not go through our standard editorial process and may contain inaccuracies and grammatical errors.