Also serving the communities of De Luz, Rainbow, Camp Pendleton, Pala and Pauma

Roses are blooming but watch out for fungi

Many gardeners are having – or are about to have – their first flush of blooms. Climate change is influencing the weather and effecting the accustomed pruning schedule. The erratic temperatures also have a bearing on the growth of the plants. Roses didn't stop growing this past winter. I was one of those gardeners who pruned later than I had hoped.

Even so, I have buds opening on the bushes that were pruned on schedule. Now the conditions for fungi are present, and rust and/or mildew which will need control with fungicides – and even stripping infected leaves if the infestation is heavy. I have had reports of rust and thrip activity in some areas, so inspect for these daily. The prediction for higher than normal temperature for the next two weeks may help with fungi problems. Other things to watch for are rose mosaic virus, black spot and Anthracnose.

If you want the fullest blooms possible, supply plenty of water to your plants, but don't flood them. For larger blooms, apply greater amounts of water when buds begin to swell and show color. But pay attention to the drainage of your soil – roses like plenty of water but they don't respond well to soggy soil. The optimum time to irrigate is early in the day.

Roses love food. Preferably good quality food on a regular basis. Not all fertilizers include all the micro/macro nutrients needed, so read the label on the packaging. Alternating the major fertilizer with fish emulsion every two weeks will help provide some of the micro nutrients. As I always say, organics are much better for the soil and ultimately for the garden and the environment. Sprinkling 1 cup of Epsom salt (Magnesium of Sulfate) around large size plants, 1/2 cup for smaller plants, once in spring and once in fall can assist in getting new basal breaks – new canes from the bud union.

The soil needs a supply of organic material such as humus incorporated into the depths. That amendment isn't easily accomplished in established gardens, however adding a 3-4 inches of a good composted mulch over the entire garden, leaving a 12-inch diameter circle open around base of each bush will go a long way to enriching the soil overall because over time earthworms help transport that mulch down into the soil where the microbiology is complex and multi-tiered.

A healthy garden soil system is teeming with beneficial microbes that inhibit, compete with and consume disease-causing organisms. It creates a sustainable soil "immune system." In fact, plants grown with organic fertilizers are themselves more resistant to pests and diseases. In addition, when you feed those beneficial organisms, they feed your roses. That's because they are busy breaking down organic matter and releasing mineral nutrients slowly and reliably. I've recently learned that extra phosphate in the fertilizer that you use is most important in assisting in creating a soil environment that aids immensely in helping plants to be resistant to pest and diseases. Also helping plants to develop hardier root systems and larger blooms.

Many gardeners become discouraged when they first experiment with organic treatments while still using chemical fertilizers. It is difficult – in fact, almost impossible – to have it both ways. Chemical fertilizers negatively impact the soil food web by poisoning entire portions of it. The fact is, chemical fertilizers are salts. What gardener hasn't seen what table salt does to a slug or snail? Salts absorb water and dehydrate the soil microbes which are the foundation of the soil nutrient system. Once you've used chemical fertilizers regularly, you must keep adding more because the soil microbiology is weakened and unable to do its job of releasing naturally available nutrients to your plants.

Rains help to leach accumulated soil salts from the soil, provided there is sufficient drainage. Organic fertilizers and amendments, such as manure, compost or mulch, break down slowly, generally staying where you put them, and don't contribute to groundwater pollution as long as you prevent run off into drains. In addition, they improve the soil food web, so in the long run you end up using less product.

Chemical fertilizers are artificial growth stimulants and, in the long run, harm your soil and pollute local waterways because as dissolved salts they quickly leach through the soil becoming unavailable to your plants and enter the groundwater. How about swearing off chemical fertilizers for the rest of the year and starting to use organics? Give it a year. See if your roses don't reward you. Fish emulsion is also a good amendment to apply either to foliage or onto the soil around each bush.

You may have had some blooms already. Keep spent blooms cut away. Cut the cane back to an outward facing bud at a three to five leaflet leaf for new growth. Air circulation is important to help prevent fungi diseases. The small spurs growing inside the bush can easily be finger pruned to keep the center of the bush free of extraneous growth.

Giving the bush an early morning shower to rinse off the leaves may help to avoid powdery mildew. Do it early enough that the leaves will dry before the sun gets hot. It is possible that with nighttime dew a disease called Botrytis can appear as discolored spots on the blooms, especially on blooms with 40 or more petals. Remove these as soon as disease is noticed. Even with great observations and preventive methods, fungi may become a problem and chemical treatment may be needed to keep disease at bay. Make sure to deep water. An extended slow watering is more beneficial than a frequently short application.

With the relaxing of social distancing and masking, rose societies are beginning to hope for regular meetings and maybe even rose shows. San Diego Rose Society is planning a June district rose show. Much depends on availability of venues. There may be other rose happenings still unannounced, watch for any opportunities in the next month or two to attend local rose shows and see, learn, smell different varieties.

For more ideas, visit TVRS' Rose Haven garden at 30592 Jedediah Smith Road., in Temecula, as well as at http://TemeculaValleyRoseSociety.org/index.shtml. Spread the joy of roses.

 

Reader Comments(0)

 
 
Rendered 03/29/2024 01:08