Summer is Here! - Summer Rose Tips

Proper summer rose care involves fertilizing, weed prevention, watering and a preventative spray program.

Fertilizing: Here’s a subject that has filled chapters in rose books. Once again, it’s a topic that can be boiled down to four basic rules. 1. Feed the soil. While supplying nutrients to the bush is important, feeding the bacteria in the soil that breaks down fertilizer into a form that your roses can consume is equally important. Be sure to give your roses a dose of organics early in the season to spur bacterial life in the soil. Horse manure or an commercial organic formula like Mills Magic will do the trick. You should also include your favorite rose food at the same time. 2. Supply micronutrients. The N, P, and K in your favorite 10-10-10 fertilizer isn’t enough. Roses also need micronutrients, much like humans need vitamins. Ironite makes an inexpensive fertilizer that supplies iron and needed micronutrients. 3. Feed often. Roses are heavy feeders. It takes a lot of energy to make all those rose petals. Roses should be fed every 4-6 weeks with organic compost that will loosen the soil. Start fertilizing your roses when you have done your first pruning of the year..

Weed Prevention: Warm summer temperatures break down mulch quickly. If your mulch is getting thin, now is a good time to put on a couple of extra inches. Grass control can be achieved with Grass-B-Gone, or Ornamec Over the Top - both will not harm roses if a little over spray reaches the leaves. Have a problem with nutsedge? Manage will kill the nutsedge while a little overspray will hot harm your roses. Broadleaf weeds need to be pulled, or covered and smothered with mulch.

Use Rose Care products to prevent disease: Start your spray program with your first pruning of the year.

Use a contact fungicide: These are compounds that kill the black spot fungus as well as its spores on contact. Manzate and Mancozeb are two of the more popular contact fungicides.

Use a systemic fungicide: These are compounds that prevent the germinating black spot spore from taking hold on the leaf. While systemics do not kill the spores, they do stop the fungus dead in its tracks by interfering with its metabolism. The fungus can’t digest its food and soon dies. Popular systemic fungicides include Banner Max and Compass. Mixing a contact and systemic fungicide in the same sprayer works well. By killing off spores and preventing the growth of any existing fungus, black spot is quickly eradicated. Although using both a systemic and a contact fungicide is the key to controlling black spot, don’t make the mistake of using the same systemic and contact fungicide each time you spray. Just as bacteria have become increasingly immune to antibiotics, the black spot fungus is becoming resistant to some of the compounds used to control it. To ensure that an immunity does not develop in your garden, switch off the fungicides you use each week. Here is a list of some of the more common systemic and contact fungicides that control black spot.

Contact Fungicides

• Mancozeb/Fore
• Manzate/Maneb
• Daconil
• Captan
• Copper Sulfate

Systemic Fungicides

• Banner Max
• Compass
• Clearys 3336F
• Immunox
• Triforine/Funginex

Caution: All rose care products can be harmful if misused. Be sure to read the label and follow instructions carefully.

Water: Roses need lots of water during the summertime. A couple of inches a week is a good guideline. Watering with a soaker hose or drip line is preferred because moisture does not contact the leaves. Over the top watering soaks the leaves leaving them susceptible to fungus attack and washing off rose spray. Over the top watering should be avoided if other options are available.

 

..Consulting Rosarians

Consulting Rosarians are expert rose growers who have passed an exam by the American Rose Society. They are there to help you with your rose growing problems at no cost to you.

If you have a question for one of our consulting rosarians, please fill out the form below and we will do our best to answer it.

If you would like a consulting rosarian to visit your garden to discuss your roses, be sure to include your name, phone number, and the area of town in which you live. A short description of the problem you are having would also be helpful.

 

Enjoy the Winter 2009 '09 issue of Rose Petals.
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