Question
I live in the high desert in california my honeysuckles i planted this spring are now getting yellow leaves with brown spots i have given them iron but it seems to be getting worse. They are north facing and get light all day.
can u help

Thanks margaret

Answer
Hi Margaret,

High Desert in the wintertime!  Must be lovely weather.  

Upon examination of your leaves, are these brown spots on certain parts of the leaves?  For example, do they appear on the top of the leaf? the bottom?  Do the brown spots ever develop into "holes" that completely pierce the leaf?  If so, those are signs of a fungal infestation.  

The rather vague symptoms that you describe can also be related to stress.  You mentioned that you used iron on the plant.  What was the indication that you needed to supplement the soil with iron?  It is common to find hi pH in western soils which effectively locks out the iron from use by the plant.  So, resultantly, if you have an alkaline (high pH) soil, applications of iron will not be effective.  

If you are sure that the chlorosis (yellowing) of the leaves is related to nutrient/environmental conditions, then you need to adjust the soil acidity to be between 6.0 and 7.0.  Iron is easily used in this pH range.  You can purchase pH kits to assist in determining soil acidity.

There is always the added complication that in the wintertime, irrespective of the compass orientation, plants always receive less sunlight.  These brown spots may just be an effect of the change in the environment.  Most honeysuckles are evergreen, and the ones in my area, do have yellowing leaves and small lesions at times during the year.  

Depending on your temperatures and the species, you should see new growth in late February or early March.  If you do not, that would indicate a more serious problem.  

Examine carefully for insects and fungi, but in the winter, these pests/pathogens have reduced metabolism as well, so the effects will be minimized.

Good Luck.