San Diego Rose Society
Established 1927
An Affiliate of the American Rose Society
Basic Rose Care
The San Diego Rose Society has been helping folks to grow and enjoy roses since 1927. The articles listed here are only a tiny portion of the wisdom and guidance we provide to your members. We hope you find them helpful -- and we hope that you will consider membership in SDRS as a way to do something wonderful for your roses and yourself.
Dick Streeper's 2008 Calendar of Care
Caring for Roses:
Basic Rose Care etc.
Good all-around article for those starting out with roses.
Pests and Pestilence
A great compendium of wise advice from Phil Ash, a man who once bragged that he had the most complete collection of rose diseases in Southern California!Disease and Abiotic Disorders
Article from the University of California Statewide Integrated Pest Management Project. You'll learn to identify some common rose diseases. (By the way, "abiotic" simply means "caused by something that isn't alive" such as sunburn and frost damage.)Cultural Practices and Weed Control
Another UC article that includes tips on selecting roses, soil composition, and many other topics.
Insect and Mite Pests and Beneficials
UC article that includes warnings on the use of chemicals, as well as guidance for using natural insect enemies to control insect pests.
Questions and Answers
You've got questions, we've got answers! The Q&A listed here is drawn from our award-winning newsletter Rose Ramblings. When you join SDRS, you'll automatically receive the newsletter and gain access to our Members Only portion of this site.
Click on a topic in this mini-menu to go directly to questions and answers on the topics you're wondering about.
Books and Other Information
Blossom Problems
Finding Good Roses for San Diego
Starting (Propagating) Roses
Planting Roses
Diseases, Pests, and Pest Control
Weeding
Pruning Roses
Ask a Question
Books and Other Information
Q: I would like to have one book on basic rose culture. What should I buy?
A: The best basic book for San Diego is the Sunset book, "All About Roses."
(Source: Where Can I Find?, Rose Ramblings, Jan 1997)
Blossom Problems
Q: On some of my new blooms, the bloom doesn't grow straight up, it bends 90 degrees and develops like it is really watching me to see what I'm doing. Why the 90 degree bend?
A: Isn't it nice to know your plants want to watch you? I've heard two basic explanations and neither one may be accurate. The first suggests that powdery mildew infected the area just below the bud and caused the turn. The second is that one of the sepals, the green things going up around the bud, doesn't let go, remains stuck to the bud, and as bloom growth continues the bloom is pulled sideways. Take your choice or if you have a better explanation please forward your answer to the Editor, who will ensure that I am informed!
(Source: CR's Corner, Rose Ramblings, Sept 2001)
Q: Do you have any ideas what made this Rouge Royale so distorted?
A: Yes, it is what is called a vegetative center; a new bloom is reblooming right in the center of the original bloom. Cause, pick one: too much fertilizer, genetic malfunction, somebody somewhere doesn't like you, etc. Cut it off like it was a normal bloom and let the process start again; it probably won't repeat.
Q: I have a hot coral climbing rose bush that I planted about 4 years ago. It's beautiful and healthy and produces tons of bright hot coral double bloom roses. This year, the first color I saw on this bush was a dark burgundy red. I thought my bush got cross-pollinated. But, the burgundy roses are single bloom roses. The leaves are even different. Darker and smaller than my coral rose bush. My coral colored roses are also blooming. It's obvious that I have two rose bushes growing from the same place.
My question. How did this other rose bush not only get started here? Also, it's just as big as the coral rose bush. How? There is a rose bush like the burgundy one in the neighborhood, but it is down the block and across the street. It looks like the same roses that are now growing in my yard. I'm stumped!
A: Your letter is an absolute classic and I started laughing as I read the first line in the second paragraph! You have now met Dr. Huey and it sounds like a tie! Your neighbor has also met Dr. Huey.
Many roses grown in Southern California are grafted roses. A small piece of the rose that will be for sale is grafted onto a rootstock rose, variety Dr. Huey. At the start of the second year in the growing fields the top part of the root stock rose is removed and the rose you are going to buy takes off and grows, is harvested, packaged, purchased, planted, and enjoyed, until a sucker comes out, or two or three or however many. These come from beneath the bud union which is where the graft took place. Coming from beneath as long whippy green canes, they can be mistaken for something good. They are suckers!
Suckers are not what you paid your money for. You paid for a hot coral climbing rose. Just as your neighbor paid for something else not Dr. Huey. The school solution to your problem is to dig, if necessary, down to where the dark purple flower cane is attached and cut off the cane as close as you can to the root stock. Do that with all the long whippy canes with purple flowers. The cane is different as are the leaves from those of the hot coral rose. If it comes from below the bud union lump, cut it off. It may well come back so be prepared and take it off again.
Lest you think there must be some mistake, I assure you I have a Dr. Huey rose deliberately growing in my back yard. The single petal (5-12 petals), purple flowers with the white stamens (in the center of the bloom) are attractive; it is a climbing rose. I have even entered it in rose shows.
You could always decide that you like the effect and keep both roses. At some point Dr. Huey will take over and the rose you bought will gradually disappear. I would suggest you break the news gently to your neighbor down the street. The fact is this happens fairly often and there are lots of "purple bloom" roses in San Diego!
Finding Good Roses for San Diego
Q: I am interested in buying a less-than-common rose variety. How can I find a person who sells it?
A: The Combined Rose List contains a list of virtually every rose variety sold in the world at this time. It includes a small amount of data concerning the rose and the name, address, and telephone number of all nurseries in the world which sell it. The Combined Rose List can be bought from Peter Schneider online or at: PO Box 677, Mantua Ohio 44255. Another source of info is HelpMeFindRoses. Also, go to our link for Best Roses.
(Source: Where Can I Find?, Rose Ramblings, Jan 1997)
Q: I am interested in seeing which new roses grow well in San Diego. Where can I see the new varieties?
A: The Inez Grant Parker Memorial Rose Garden in Balboa Park grows most of the significant new varieties beginning about one year prior to commercial introduction. It is your best source of evaluating new varieties prior to their introduction onto the market.
(Source: Where Can I Find?, Rose Ramblings, Jan 1997)
Starting (Propagating) Roses
Q: Can you start a new rose plant off of a mature one? If so how is this done?
A: Yes, most of the time. Basically, cut off a spent bloom (petals falling off). Count down 4 leaf sets and cut it off. Pull off the bottom 2 leaf sets. Put the cutting halfway into a 1 gallon pot of potting soil. I put 10 cuttings per pot. Keep the soil moist. On the coast, put the pot where it gets 3-4 hours sun: don't let it fry! After 6-15 weeks, you will either have a cane sprouting new growth or the cane will have turned dead-brown. When you see little roots coming out of the bottom of the pot, take the cuttings root ball out and carefully break apart the ones that are growing. Put each of them in their own 1gal pot and when they have bloomed, you can plant them wherever you'd like. For details, see this link:
http://www.ars.org/About_Roses/propagation.html
Planting Roses
Q: I took out some roses. Can I plant new roses in the same holes?
A: Sure. Clean out the hole, pulling out any of the old roots you find. Refresh the soil with fresh amendments. Put some superphosphate and sulfate of potash in the bottom and cover it up. Plant rose. Enjoy new rose.
(Source:CR's Corner, Rose Ramblings, Mar 2001)
Q: What are suckers?
A: (a) Folks who believe that the color photos and descriptions in the rose catalogs are what's going to grow when they plant it in their yard! OR (b) A long whippy green cane of ovoid leaves that shoots out of the ground, actually growing from the root stock rose, beneath the bud union. Keep it around long enough and it will have a dark purple, fragrant flower. Grab the cane with gloved hands, close to the ground, and TEAR it off. Cut it off and the 2 budeyes on either side will produce 2 long whippy canes. Tearing, hopefully, pulls off some of the neighboring eyebuds.
(Source:CR's Corner, Rose Ramblings, Mar 2001)
Q: All my roses are in pots. Recently, some of them have dirt coming out of the holes at the bottom. Is this a bad thing, and what causes it?
A: Sure it's a bad thing. The dirt level in the pot goes down. The dirt goes all over the patio, etc. The water moving through the pot carries some dirt with it and flows out the holes. Cut 4" by 4" squares of Weed Block or screen material and place over each hole inside the empty pot. Fill with your potting mix and a rose. Then when you water, most of the dirt will stay inside the pot.
(Source:CR's Corner, Rose Ramblings, Jun 2001)
Q: Is it okay to transplant a tree rose from the ground to a pot?
A: Sure, as long as it's a well-behaved rose in a big-enough pot. Lynn Anderson (average cane height 10' on top of a 5' tree standard) will slightly overbalance the pot. But you could put it down on the first-floor patio and cut blooms from a second-story window.
(Source:CR's Corner, Rose Ramblings, Mar 2001)
Q: Can you plant rose hips?
A: Sure, but that's the hard way. When the hips are ripe (orange to red), pick them. Carefully cut open each hip and remove the seeds inside. Spread the seeds out flat on a damp paper towel, cover with another damp piece of towel and place in a plastic bag. Put the bag in the vegetable section of your refrigerator for 30-45 days, then plant in a black flat filled with good sterile potting soil about 1/4 inch deep. Place in a sunny location and keep the soil moist. Some but not all of the seeds will germinate in 6-12 weeks. When the little seedling has a couple of leaves, carefully transplant it into a small pot. Keep moist, sunny, watch and see what develops.
(Source:CR's Corner, Rose Ramblings, Nov 2001)
Q: Someone said I shouldn't put my potted rose in a saucer. I don't want the dirt all over my patio. Help!
A: The rose sits in the saucer. When you water, it drains through and the pot winds up sitting in an inch or more of water. That begins the process known as drowning the roots of your rose. Drowning roots can't do anything useful except die and smell bad. BUT, two thoughts. First, putting a piece of screen wire or Weed Block in front of each hole inside the pot just before you put soil in helps keep it in and lets only water drain through. Second, use the saucer but raise the pot so that the base is above the water level in the saucer. Use brick, rocks, pieces of wood to raise the pot.
(Source:CR's Corner, Rose Ramblings, Nov 2001)
Disease, Pests, and Pest Control
Q: Can I use BT (Bacillus Thuringiensis) on my roses to get rid of leaf chewing caterpillars and tiny moths? The leaves look very holey all of a sudden. I have to mix some BT to put on my petunias anyway, and thought I might treat both with BT.
A: Yes, yes, yes. Unless the spray label says don't mix with other chemicals, you can use BT alone or mixed with almost anything you spray from Funginex to Citrall. Don't be disturbed when the crawlers don't die instantly. It takes a couple of days from the first bite of BT to go thru the process of locking up their stomachs and starving them. Has to be a true caterpillar for the stuff to work so the moths will continue to lay eggs which turn into larval stages which can then ingest the BT. BUT, most of the little tiny holes and small window pane like gouges on the rose leaves are caused by rose slugs, the larva of the saw fly. Rose slugs are flat, little (less than 1/2inch in length), on the undersides of the leaves. Rose slugs aren't caterpillars, which I learned after spraying them 5 times with BT and getting zero results. For the lacy leaves done by the slugs, get a spray with Pyrethrin in it, like Safer's Yard and Garden Insect Spray; look for Pyrethrin at the Ingredients part of the label. Some folks tell me they are also having good luck when attacking the rose slugs with light horticultural spray oil or Envirepel or neem oil. If it's a caterpillar get the BT; if it's a rose slug, get the oil.
Q: A bunch of leaves on my roses have suddenly started turning bright yellow. I didn't water for a couple days and it got really hot. Did I kill them? Will they bounce back?
A: Sure! Roses turn yellow for lots of reasons starting with old age, too much or not enough water, most reasons not being fatal. Right now (June) as really warm weather approaches, I'd check the underside of those yellow leaves and see whether it looked like they'd been sprinkled with salt and pepper. If so, I'd get out my magnifying glass and look for spider mites. Finding them, I'd start a regular program using a watering wand upside down spraying the undersides of the leaves to knock the mites off. Do it 3 - 4 days straight and then periodically to keep them off.
(Source: CR's Corner, Rose Ramblings, Jun 2001)
Q: I have all different sized holes in my leaves and I almost never see anything chomping on them. What's going on?
A: You've got a bunch of different insects in different stages of development eating different size holes, while you are sitting watching television or have gone to bed. After dark, get your flashlight and go out and see all this activity going on as well as exactly the critters doing it. You'll find at least four sizes of little green worms, a bunch of chomping beetles, enormous grasshoppers, earwigs, slugs, and even an occasional snail. If you are into revenge, start picking them off, squishing them between your thumb and forefinger, and dropping the remains in a bucket. Carry paper towels for obvious reasons. You can hose them off or knock them off. You can spray with toxics if you have to, but washing off is something that the roses and your neighbors will approve of.
(Source: CR's Corner, Rose Ramblings, Sept 2001)
Q: Help! I think my roses are suffering from rust. What can I do?
A: Pull off all the leaves with rust when you first see them. Assuming you are beyond that stage, two ways to go. First you spray toxic chemicals or second, you spray non-toxic chemicals.
Going the toxic route: Get Funginex (a dangerous fungicide), a respirator mask, goggles, rubber gloves, long sleeves, long trousers and a tank sprayer (1qt to 1+ gallons depending on the number of roses that you have) and blast away being sure to hit the underside of the leaves. This may work. Or on the internet look for PlantVax, a chemical not sold in California, and using all of the equipment above, blast away. This will work.
Going the non-toxic route, get Rose Protector, which should be at Armstrong's, Walter Andersen's, Kniffngs Discount Nursery and other good nurseries this weekend, it's a new product. It comes as a concentrate, in a hose end sprayer bottle, or in ready to use form (if you have a small number of roses). Wear gloves, stay up-wind so the spray blows away from you. Blast away being sure to hit the undersides of the leaves. This make take several applications several days apart but should work.
The magic words are "may, will, and should."
(Source: Consulting Rosarian, email to Web site query, March 2003)
Weeding
Q: My roses are in pots and I keep noticing weeds starting to grow in each pot. Can I just pull those out or will it damage the rose roots? Help!
A: When the weeds are small, their roots are quite short. This is the time to pull them out. The roots will come out better in moist soil. They will be even easier to pull out if they are growing in a 2 - 3 inch layer of mulch. There are pre-emergent weed killers, which you might try. Read and FOLLOW the label directions. Be sure the label says OK to use with roses. Do not under any circumstance use Roundup as any overspray onto roses kills the plants.
(Source:CR's Corner, Rose Ramblings, Apr 2001)
Pruning Roses
Q: I pruned in January/February, and I already have some buds but they are on REALLY short stems! What caused this?
A: Growth aberrations like that occur when the weather, usually the temperature, is wrong at the precise moment a particular growth activity is taking place. The cold slows the growth. A frost nips the tender growing tip. If you like short stems, let it grow. There is also a class for floating blooms in our rose show. Nobody can see how short or lousy looking the stem or foliage were as the stem is totally cut off.
(Source:CR's Corner, Rose Ramblings, Apr 2001)
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