With the arrival of June, we are seeing our first bloom cycle of the season come to an end. In our garden, we enjoyed one of the best spring bloom cycles we have had in several years. The roses were absolutely stunning!
Now that the first blooms are fading, it is time to deadhead and remove all of those spent blooms. This will encourage new growth and, more importantly, a lot more blooms. When removing spent blooms, we recommend cutting at a 45 degree angle about ¼” above the first leaflet (with at least four leaves) below the bloom. Also, as you remove spent blooms take a few minutes to look at the bush and remove all the twiggy growth that will do nothing but provide a good home for spider mites and disease. Be especially careful to remove all the spindly growth that is at or near the base of the plant. In addition, remove any canes that have died. Finally, try to open the center of the plant to promote good air circulation. This will help to minimize disease and insect infestations. This whole process will go a long way towards putting your bushes on the right path to a great rose season.
If you experienced brown edges on your rose petals, especially the lighter colored blooms, odds are you have thrip. These tiny but pesky critters attack your buds. They feast on the bloom petals which turns them brown, especially on the edges. Many rosarians mistakenly think that the brown edges on their blooms were the result of a fungus, while in fact if they will dig down into the bloom, they will find thrips having a field day. While there are several insecticides that will help control thrips, we recommend using a product that contains spinosad as its active ingredient. Spinosad will not kill all of the good predator bugs that are in your garden eating the bad bugs. Bonide markets a product named Captian Jack’s Dead Bug Brew which has spinosad as its active ingredient. Ferti-Lome also markets a product named Spinosad. Of course, if you have a large garden you might want to check out Conserve SC, however it is pretty expensive. When applying any of these products be sure and focus your spray on the buds and blooms as that is where the thrips are.
May was a rather cool month. These conditions are perfect for fungus in the rose garden. Cool weather can bring on botrytis, which can rot your blooms. If this is the case, you should go ahead and remove the rotting blooms. As the weather gets more consistently warm, the botrytis will subside.
Typically June is the beginning of the hot and dry season in the tri-state area. When you do not get sufficient rainfall, it is very important that you provide water for your roses. When the temperatures reach the high eighties, the roses will need 2 to 3 inches of water a week. There is nothing more important than keeping your roses well hydrated. Make it a priority and your roses will reward you.
Our roses have used a lot of energy to produce that first bloom cycle and they are hungry! We also need to keep in mind that we will get most of our new basal breaks right after the first bloom cycle. To keep the roses happy, we like to use a granular fertilizer relatively high in nitrogen, say 12-6-6 or even 10-10-10 scattered around each bush. To keep your plants’ roots from burning, always remember to water before and after any application of a granular fertilizer. We also like to include liquid fertilizers in our feeding program. There are plenty of good products on the market such as Mills Liquid Easy Feed, Peters 20-20-20 and Peters Super Bloom, so pick one and use it. We are also adding organics such as fish emulsion, liquid kelp, and seaweed extract to our liquid feeding program. You can also apply another round of organic fertilizers around mid month.
Spider mites are beginning to make their presence known. The best way to keep spider mites under control is to spray the undersides of your rose foliage with a sharp and relatively forceful spray of water. Do this in the heat of day and it will not only eliminate the mites, it will also cool down your roses as well as you! If you have a lot of spider mites, use water every three days for three cycles and that should do the trick.
Pretty soon we will probably begin seeing our friends, the Japanese beetles in the garden. In fact, as I write this, we have already found 2. That doesn’t sund too bad, but they can come quickly and in bag numbers. If you don’t have many beetles, you can stroll through your garden daily and shake them off into a container of soapy water where they will drown. Other options include spraying your plants with Bayer Rose and Flower Insect Killer every week. You can also use Sevin, however we do not recommend it as Sevin will also kill your beneficial bug population. Japanese beetles seem to enjoy the more fragrant blooms the most; therefore, we leave these blooms on the bush a little longer, thus attracting the beetles where they are easily killed. This helps us to minimize the area of treatment. Of course, if none of the above methods appeal to you, then you can always choose to do nothing and just learn to live with them until early August.
If you are experiencing blackspot in your garden, we recommend that you spray every three days with Manzate, Dithane or Mancozeb for a two week period. After a couple of applications, some rosarians who are still seeing outbreaks of blackspot, complain that their treatments aren’t working. You must remember that blackspot spores can take up to 15 days to affect your foliage. Thus, it may take up to three weeks or so before you stop seeing new outbreaks of the disease.
Finally, the roses that last the longest are the ones you share with friends. Don’t forget to take time to smell and enjoy your roses!
We are returning to “in-person” meeting on June 24 at Trinity Lutheran church in Hixson. More detailed information can be found elsewhere on the website. We always welcome visitors!