Orchid Diseases (2)

 

Phalaenopsis Bud Blast
This is a condition where a seemingly healthy phalaenopsis orchid spike develops buds that do not fully open and turn yellow or shrivel and drop off.

The cause can be many things, the most common is root rot. Hot or cold drafts, over fertilizing, softened water and a number of other conditions including exposure to smoke from burning leaves or barbeques can be attributed to bud blast.

Pseudomonas Cattleyae
Pseudomonas cattleyae, also known as 'brown wet spot' occurs mostly in phalaenopsis. However, a similar wet bacteria infection can occur on other orchids as well.

Plants develop brownish black, soft areas usually starting on the underside of the leaves and quickly penetrating to the leaf surface. The cause is a combination of cool temperatures, high humidity and inadequate air movement. Prevention is easier than the cure. Keep minimum night temperatures around phalaenopsis at least 60 to 65 degrees F along with brisk air circulation. Brown wet spot can not develop under such conditions.

Remedy: If the disease has reached the crown portion of the plant, there is no cure even if some of the leaves look healthy. On phalaenopsis, if caught early, the affected portion of the leaf should be cut off (well below the afflicted area) with a new razorblade or some other sterilized cutting tool. Wet rot on other orchids must be treated by lancing and then cutting and/or scraping out the damaged tissue.

Orchid Virus
This is the most dreaded orchid disease because it can not be visually identified in its early stages. Orchid virus disease invades and kills leaf cells which condition in turn facilitates secondary bacteria infections. The disease has no preference to type or genus and can spread from plant to plant indiscriminately by insects or cutting implements. In the advanced stage, orchid leaves will display ugly black rings, circular or diamond shaped spots.

Unfortunately, there is no remedy or cure for orchid virus and the only positive way to know if your plant is infected is through laboratory testing. There are many other causes for black discoloration on orchid leaves and that condition in itself does not necessarily mean that your orchid is infected by virus.

Maintaining consistently clean growing conditions along with common sense cultural practices including optimum temperature and climate, will go a long way towards keeping your orchids healthy and in top condition.

What is the best way to deal with bacterial and fungal disease on my orchids?

The most efficient method to treat bacterial and fungal disease is the regular use of a systemic agent such as Phyton 27. The agent will be absorbed by the roots of the plant and then carried throughout the plant. Once the Phyton 27 is absorbed by the plant it will remain in the plant~s system for months.

How can I prevent bacterial and fungal diseases?

Orchids benefit from fresh air circulation. In their natural habitat, orchids get excellent air circulation, which helps prevent bacterial and fungal diseases. Avoid cold drafts from coming in contact with the plants as well.

Try to water the plants early in the day, so that the foliage will be dry by nightfall. To prevent bacterial and fungal disease use Physan 20 once a month.