This article was written by our Master Rosarian, Lynn. It was part of the August News letter. (Click here to read the letter.)
This is the time when we get so busy with other things from work to vacations to kids going back to school shortly that it is easy to let the roses take a “back seat,” and that’s when things can go wrong. If your roses don’t receive the proper water, they will be stressed, and that is just when the spider mites take advantage…and take hold.
Remember to Wash Your Roses
Like humans, roses like a bath, getting the undersides of their leaves cleaned off, and even the tops. With all the drought we are experiencing, there seems to be dust everywhere, and a shower in the morning hours allows the plants to dry off thoroughly before evening and also before any extreme temperatures could burn the leaves where water droplets remain. I can’t emphasize enough the need to WATER, WATER, WATER.
I know we are blessed with a good water source and many other places around the country are telling people to conserve and only water on limited days and for certain amounts. Even here I have heard of wells dropping in water levels, so it could be a problem for those people if we don’t get our much-needed rains this fall. All you need to do is look at the weather maps and see how much of the western part of the United States is being hit with the extremes of drought and heat to know we are not alone!
About Those Darn Spider Mites
Spider mites are not to be ignored. If you have an infestation of them, they will defoliate the plant quickly. Look for dull-looking leaves, leaves that have lost their shiny look. Then turn the leaf over and you will see fine webbing. A check with a hand-held microscope will make your skin crawl as you see these little two-spotted critters enjoying sucking the life out of the leaf.
I found Grower’s Edge Illuminated Microscope, 60x – 100x on Amazon at $19, plus tax and shipping, which looks similar to the one I used to recommend at Radio Shack. Their stores are no longer available here, and a search of their website brought up nothing like what I have. Anyway, if you want to get a close-up of these nasty critters, the Grower’s Edge product might be something you would like to check.
Back to the problem, though. You don’t want to just let nature take its course with spider mites. The leaves are the food factories for your roses, and going into winter in a “hungry” state is NOT a good idea. Keep your roses healthy, and in this case you have a choice of using a water wand every two or three days, spraying with a strong fine spray up under the leaves to wash off what you can, or using a miticide.
Some of the systemic fertilizers claim to be effective, but unless they have a specific miticide, not just an insecticide, they won’t do the job. I have read that a solution of equal parts of rubbing alcohol and water will kill the mites without harming your roses. I have not tried that, but again, I have not seen spider mites in several years, probably because I have not used products such as Sevin that kill the beneficial insects.
I know it is not my eyesight that is the problem, as I definitely would see leaves drying up. One other organic solution I saw was to make a spider mite spray by mixing 1/4 cup vinegar, 1 tablespoon baking soda and a few drops of liquid dish soap in 1 quart (1 l) of lukewarm water. Spray wherever you see evidence of spider mite activity until they are completely gone. (This will also work on most insects and pests.)
Again, I have not needed to try this, so I have no idea how effective it is. I might add a warning here: If you decide to purchase a specific miticide product, not a combination chemical, they run over $100 on one of my trusted sites, rosemania.com, so if you have a small garden this would be a last resort, as the miticide is in a quantity more than you will ever need. It is best to try the water spray method or a water wand. You don’t want to waste your time with the shower head type of water wand, as the spider mites may just sit there and laugh at you as they take a bath!
You can check “high pressure water wands” on the Internet, and look for the kind that has a flexible end so you can turn it upward, under the leaves. They are around $20, so it isn’t a huge expenditure. Whatever you do, don’t ignore the problem, as the spider mites multiply at alarming rates. They seem to enjoy miniature roses, but I think it is because they are close to the ground and easy to navigate.
How About Some Alfalfa Tea and Fertilizer?
Fertilizer, in the Spokane area, was applied for the last time in mid-July, but that was only regarding the granular types. If you see your roses need a perk-me-up you might want to make some alfalfa tea for them.
To make alfalfa tea…
- put about eight to ten cups of alfalfa meal or pellets into a 30 gallon plastic garbage can,
- almost fill the can with water, cover and let bake in the sun for three to five days.
- You can add a tablespoon of instant fertilizer such as Miracle-gro, stirring it in well (there are 16 tablespoons in a cup if that helps in your measuring, so 1 1/2 cups of Miracle-gro will work) and …
- apply a gallon of this to each large rose or about half that for the miniatures. Alfalfa contains a growth hormone called triacontanol and is recommended as a spring tonic to make the roses more robust and healthy.
But Aren’t Roses Fussy and Difficult?
Having said all these things, I want to add that roses are not the fussy, fragile plants some would like to portray. They are shrubs, and if you want boring then just plant some evergreen shrubs around your yard, but they will give you no more color than the greens and yellows. They also like water, and they harbor other insects.
Yes, you can have a yard service come to spray your evergreens and lawn during the summer months, but there is still that lack of color and often fragrance to make you want to spend time outside enjoying your garden.
If you have grown roses for a number of years, you know what I mean. My own home garden has around 200 rose residents of all types, sizes and colors. Every spring I can’t say I look forward to pruning all of them, but as I get into it I find my body is more limber, so at 80, as long as I can prune my own roses I intend to continue on.
This past spring brought on a more brilliant display than I believe I have ever seen… that is until we got the 100+ temps the end of June, and that brought a sudden end to the display. But again, roses are resilient and now they are giving me the last hurrah before – dare I use the foul word – winter!
Enjoy the roses! They are not finished showing off their beauty for some time yet this year.
A Couple of Videos on the Spider Mites
This one covers the basics of the mites, as well as control.
This video is similar, but goes into more detail. About 20 minutes long.