Let me start off by saying this always true fact: roses are FULL sun plants. Full sun means 6+ hours of direct sun per day. You hear a lot about sun conditions in the rose community. "This certain rose doesn't like this sun", or my favorite, "roses don't like too much sun". This is not true, and if you continue to read, I will explain why. Roses, as a plant that prefers FULL sun, need full sun to perform, grow, and bloom their best. If you are worried about a rose not holding up to the heat, simply plant it with morning sun only, where it receives protection from the hot afternoon sun. Make sure it is receiving a full 6 hours to get the best performance from it. You may plant a rose in part sun (which is 4-6 hours of direct sun) and have decent luck with it. You may even have a rose that gets less than that, or it may get indirect light rather than direct sun. However, roses need sunlight to bloom and grow in the way they are intended. Think how much energy it must take for them to create the beautiful shows of petals and color, consistently throughout the season! The sun is their energy source. So then, this fact frequently comes along with the title of our blog today: what is up with my blooms scorching?! I thought they liked full sun! You lied to me!
Recently, all across the United States, we have experienced our first big heat wave of the season. Here in Dallas, Texas, where One Love is located, we went from a month of heavy rains where the temperature ranged in the 70's and 80's, to a scorcher of a June where we are consistently hitting 90's and 100's. That very sudden jump in temperature can cause any plant great stress (us humans too!). I've watched even my full sun plants struggle with the huge temperature swing. My coneflowers are wilting, my salvias are sagging, and even my sedums are looking a bit worse for wear. Then, of course, come the scorched roses.
I am thinking of making this into a three part series that covers the reasoning behind these scorched blooms and wilting buds. I will break it up into three sections that will teach you a little about the science behind your garden, and what to do to help your struggling plants along in this brutal heatwave.
It will be broken down into:
1) Water
2) Soil and Amendments
3) Fertilizing and the chemistry in your garden beds.
By reviewing some basic steps you can take and some easy maintenance you can do throughout the year, you should be able to more easily understand your rose and it's needs, and help prevent your beautiful blooms from scorching entirely.
Part 1: Water
Now, I don't know about you, but when I see a poor plant all wilted over from the summer heat, my first instinct is to water it. That's a great instinct to have, and the proper response. But what most people don't realize is that the way you are watering may be having the biggest effect on your rose. In the plant world, there are several different types of root systems. Some, like crepe myrtles, clematis, groundcovers, and low growing sedums and succulents, have a feeder root system. They develop shallow root systems that typically spread out along the top few inches of soil. This allows them the first chance at any moisture and the first access to any nutrients as they break down. Others have taproot systems, like milkweed, gaura, dandelions, and some types of trees. They have long, extremely thick and deep roots that allow them to access water and nutrients from deep below, surviving drought and heat. Most plants have a root system that falls somewhere between these two types of root systems, and roses are no exception. The reality is, you can "train" the root system of your roses to react how you want them to. In many cases, hot summers and deep heat are one of the biggest issues you can face when it comes to your roses. Here's where HOW you water comes into play.
If you lightly mist the soil, naturally how is your rose going to absorb that water? With its feeder roots, of course. Near the surface, shallow = feeder roots. This may be fine during the spring, but definitely not in the summer. Now let‘s say next time you give your rose a slow, steady soak and allow the water to really saturate the soil and soak down deep. What roots are going to absorb the water? The thicker, lower roots, of course! You could even say the roses’ "tap root". While roses don't have a true taproot, they do have very deep ranging, fibrous roots. If you've ever planted a bareroot rose from a reputable rose company, you know what I'm talking about! Those thick main roots get even larger and longer with time.
Here's the easy answer to encouraging your rose to cope with the heat (you may have to baby it a little!) DEEP. WATER. That's it. Wild, right? Something incredibly simple but easily overlooked or put off in haste or laziness. I know I can be a lazy gardener sometimes. We've all been there. Do I want to stand out in this 100 degree weather with a hose and give each and every rose a nice, long deep soak? NOPE. (This is where drip irrigation systems will save your lives, people. And no, sprinklers won't do it for them either!) But if you 'train' your roses with deep, infrequent soaks, their roots will stretch downnnnnn downnnn downnnnn into the ground, forming a 'tap root' of sorts. This is a key component to roses doing well in the heat. During the heat of the summer, I water two-three times a week deeply. In spring and fall, I usually don't water at all due to our frequent rains.
****NOTE: This is only for ESTABLISHED roses (2nd + year). First year roses will need consistent moisture throughout their first seasons. You can start the training process early though. Just watch your plant, it will talk if you pay attention. Wilting and scorching = bad (too little water). Yellowing = bad (too much water) *****
In our second part of this series, we will explore your soil. What on earth does soil have to do with your rose scorching? You'll see! Follow up next time to learn more about the other important things you can do to prevent scorching on your roses during the heat of the summer.
