Hi I have a two-fer! I have been trying to catch y'all at the Farmer's Market...

Asked July 18, 2014, 4:41 PM EDT

Hi I have a two-fer! I have been trying to catch y'all at the Farmer's Market but have been unsuccessful so I really appreciate a comment. 1. I have persistently yellowing leaves on a large houseplant, maybe a yew? Photo attached including a starting to yellow frond in middle right of photo as well as one I pulled when they yellow. Sitting by window. I water weekly. No apparent bugs. Problem began in May. 2. Second photo is also a persistent yellowing, mottled and eventual fall-off of leaves from my Brussels sprouts. A knowledgable fellow community gardener said it was a fungus so I have been trying to spray with a homemade fungicide (baking soda, cooking oil, dish soap) with little help. What do you think? Thank you.

Ramsey County Minnesota

1 Response

The houseplant looks like a dracaena. They do naturally drop their lower leaves and can eventually get very leggy. Weekly watering may be too much or too little depending on the temperatures and humidity in your house. What works in the winter may be way different than in the summer. The soil should be a little dry to the touch before watering. Dracaenas are very sensitive to fluoride, so if you use fluoridated city water that may be an issue. Here is a little more on growing dracaenas: http://www.clemson.edu/extension/hgic/plants/indoor/foliage/hgic1504.html and http://extension.psu.edu/pests/plant-diseases/all-fact-sheets/dracaena-diseases

Your brussels sprouts look like they have black or grey leaf spot. You might want to look for a commercial fungicide that is listed for controlling it. Homemade ones are not always effective and are often more toxic that commercially available products. Disposing of all diseased material promptly and rotating your crops by not planting any other cole family plants there for three years will help control the problem in future years.

Thanks for using Ask a Master Gardener and sorry for the response delay.