Q. My garden plants have a lot of ash on them due to the nearby wildfires. Will this hurt my plants? What about my fruits and vegetables? Will they be safe to eat?
I recommend spraying down your plants to remove any ash from the leaves. Ash (and dust) can interfere with photosynthesis by preventing light from reaching the leaves. It can also interfere with gas exchange (preventing the leaves from “breathing”)
If there is a very large quantity of ash, or if there’s a question as to whether there are hazardous substances present, or if the fire is close, you may want to forego harvesting your vegetables to be on the safe side.
Wood ash from burning vegetation is less likely to contain heavy metals and other persistent hazards than ash produced from structure fires. Ordinary wood ash can be easily washed away by thoroughly rinsing produce with water. (Vegetables and fruit should always be washed before eating in any case.) If your garden only has a light dusting of ash, this should be sufficient.
For more information:https://www.cdph.ca.gov/Programs/EPO/Pages/Wildfire%20Pages/ash-homegardens.aspx
Q. What should I be doing for my citrus trees now? They have a lot of fruit but some of the branches look overloaded. Should I thin the fruit?
Citrus trees are a bit different from deciduous fruit trees in several ways. They produce many flowers and set many fruits, but the majority of those little fruits will fall off of the tree without any action from you. Stone fruit (peaches, plums, apricots) and apples tend to set many fruits that must then be thinned aggressively to prevent branch breakage and preserve fruit quality. Citrus usually don’t need to be thinned. Their branch structure is less prone to breakage, but if you are concerned about that you can certainly thin the fruit manually.
Citrus (as well as any other perennial) should be given extra water during dry windy weather. Although they are relatively heat- and drought-tolerant, they can suffer dehydration when exposed to intense wind. Watch for curling leaves, which can indicate water stress. On the other hand, avoid overwatering, which can occur when you forget to adjust the automatic irrigation system once the rainy season starts.
If you are in a frost-prone area, take steps to protect your trees when nighttime temperatures are predicted to fall below 35F. Cover smaller trees with burlap or use incandescent Christmas lights to provide a few degrees of frost protection. If the outer leaves become damaged by frost, resist the temptation to prune them away. Those sad-looking leaves will protect the interior of the plant in case another frosty night occurs. Once the danger of frost has passed, you can trim the dead stuff away.
Fertilize in late February with citrus/avocado fertilizer. Fertilizer application tends to encourage a growth flush, so you want those new tender leaves to appear after the danger of frost has passed. As always, follow the package directions for application rates.
Los Angeles County
mglosangeleshelpline@ucdavis.edu; 626-586-1988; http://celosangeles.ucanr.edu/UC_Master_Gardener_Program/
Orange County
ucceocmghotline@ucanr.edu; http://mgorange.ucanr.edu/
Riverside County
anrmgriverside@ucanr.edu; 951-955-0170; https://ucanr.edu/sites/RiversideMG/
San Bernardino County
mgsanbern@ucanr.edu; 909-387-2182; http://mgsb.ucanr.edu