Showing posts with label diseases. Show all posts
Showing posts with label diseases. Show all posts

Monday, February 11, 2013

Basil Spots

With my mindset lately, when I saw the subject line on Chris's (a loyal listener of In Your Backyard heard on My790am.com) email, I thought to myself, "Oh no, Chris has melanoma..."  Thankfully, Chris does not but his basil isn't feeling well lately.





Here's his question: 

I planed sweet basil (from __________ )  about 3 weeks ago.  Looks like I am doing good, but I noticed some brown spots.  The soil was amended some with compost and ______________ soil for vegetables and flowers. The plant did stress/droop within the first week of initial planting, bounced back up after watering but is doing good now.  Watering is done by hand now at the base of the plant.
 Are the brown spots normal?  Due to fungus? Nutrition deficiency?
 
Thanks, 
Chris

Chris, good question and the photograph helps answer the question.  Your basil definitely is suffering from Colletotrichum disease.  The disease is identified by the black spots, black haloed rings, and black stems. It occurs when there is a combination of high humidity, lack of air circulation, and the plants are watered often. You will want to get rid of the basil plants that are affected and plant another herb or plant in that location.

When you use plant with soil amendments, especially ones that hold water well, gardeners can overwater plants.  Always check the soil before watering to ensure that you really do need to water.  Never water the soil if the ground is wet, cool, or damp.  Twice a week watering should be enough for amended garden beds in full sun.   Space plants far enough apart that they have plenty of air circulation. 

Thanks for writing Chris!
Teresa

 

Tuesday, November 29, 2011

Queen Palms Becoming Royal Pain

IFAS
I received another email from an HOA that is seeing evidence of their queen palms dying.  Since 2003, when it was first diagnosed, Central Florida has seen increasing cases of Fusarium wilt in Syagrus romanazoffiana,  Queen palms, and Washingtonia robusta, Mexican fan palm, also known as Washingtonia palm.  The fungal disease kills the palms very quickly. 

Do you think you have Fusarium wilt in your palms? Check these symptoms:
  • One-sided chlorosis.  The fronds will all be yellow or brown on one side.
  • Distinctive red or brown stripe on the stem of the frond.
  • If you cut the stem off, inside the stem is discolored especially to one side.
  • Disease appears on the lowest living fronds, moving upwards, with the youngest emerging frond last to die.
  • Palm dies within two to three months.
IFAS
The disease has been diagnosed throughout the state of Florida spread by wind-blown spores but local communities can also see many palms affected through unsterile pruning equipment. There is no cure for Fusarium wilt and rapid removal of dying palms is recommended to prevent other palms from becoming affected. Queen or Washingtonia palms should not be replanted in the same locations. 

Tuesday, April 05, 2011

April Showers Bring Relief

Last week Central Florida received abundant rainfall between six to eight inches in a three day span. The ground soaked it up! This week, we will be seeing an additional one to three inches which will go a long way to catch up rainfall lacking so far this year.  Florida's rainy season is different than our Northern cousins. Our springtime and winter are our dry seasons. Florida receives most of its rainfall in the summer and fall with daily afternoon showers and our usual tropical storms and hurricanes.  We need these torrential rain storms to replenish our aquifer systems.  We shouldn't have to irrigate in the summertime if we have normal rainfall of an inch of water a week.  But with these rains, especially in low-lying areas or in yards that are irrigated too much, we will see turfgrass and plant diseases.  Treating these fungal and viral issues after we have diagnosed them is usually too late to apply the fungicides. Fungicides are preventive not curative.  So if you usually have disease in your landscape, make sure that your irrigation system is not your watering overhead and for long periods at night. Then check your irrigation system to ensure that its watering your turf efficiently.

Here are important publications from the University of Florida IFAS for diagnosis and solutions:

Homeowner's Guide to Fungicides for Lawn and Landscape Disease Management

Turfgrass Disease Management

Brown Patch Disease November through May - All warm season turfgrasses

Cercospora Leaf Spot Late spring and summer - St. Augustinegrass

Fairy Rings Any abundant rainfall - all warm season turfgrasses

Gray Leaf Spot Late spring and early fall or excessive rainfall - St. Augustinegrass and centipedegrass

Helminthosporium Leaf Spot All year round - warm season turfgrasses

Pythium Root Rot - All year round - warm season turfgrasses

Rust - St. Augustinegrass and zoysiagrass - late fall to early spring.

Take All Root Rot - Summer to fall - all turfgrasses

We'll be discussing fungicides and disease issues on "In Your Backyard."  Call in!

Tuesday, July 27, 2010

Summertime Finds For Your Backyard

I love new plants. Especially flowers that are one of a kind that are easy to grow and look as gorgeous as candelabras on a grand piano. I found the Candelabra clerodendron at Blodgett's Nursery on Edgewater in Orlando last Friday. Its' deep green leaves and upright white flowers took my breath away. Perfect for shade or partial sun, this clerodendron is new to the market and not easily available. In fact, when I talked to Mike Gibson, with Blodgett's, he said they only had four! I think I'm going back for more!



I can't find any research on them so I'll be taking notes and letting you know how they perform in my backyard!

Another colorful shade-loving ornamental is the Persian Shield, Strobialanthus dyerianus. Very drought-tolerant, easy care, no pest issues, and provides psychedelic colors of purple, gold, green, and many other colors depending on the light. It can grow to 5 feet tall in full sun, but in the shade it will only get to be 2 - 3 feet. In full sun they will need more water and suffer stress.


I'll be talking about citrus problems in your backyard with Charles Fedunak, Lake County's Horticultural Agent. If you have orange, grapefruit, or tangerine trees, you won't want to miss it!