Garden Q&A: Pachysandra troubles and how best to fertilize
By Ellen Nibali
Mar 05, 2020 at 7:00 AM
My large established bed of pachysandra seemed fine last summer, though some wilted in the drought. It perked up when we got rain, but now almost every leaf has brown blotches. Is this a delayed reaction to the drought? What can I do?
The weakened condition of your pachysandra during the drought probably contributed to what is now a massive infection of volutella, a fungal disease. Most of the time, volutella infects old pachysandra beds where debris builds up below the leaves holding moisture and creating an incubator for the disease. Consequently, we usually get volutella questions in a wet year. In fact, the record-breaking rains of two summers ago may have started this volutella infestation.
At any rate, to renovate your bed, mow or cut it down in early spring, rake out all the infected material and the years of organic debris, then simply let it regrow. The roots are extensive and should have plenty of stored energy to accomplish regrowth. Do not let it dry out this year. Search pachysandra on the Home and Garden Information Center website.
Keep in mind that Japanese pachysandra is now considered a non-native invasive plant, and it should never be allowed to get into natural or park areas and take over. When replacing pachysandra, plant natives when possible.
We just got soil test results from one of the soil testing labs you list on your website. It says to apply 2.5 lbs. of urea (nitrogen) per 1,000 square feet to our garden. It also says to apply recommended fertilizer to the soil surface and rake in just before planting. Do they mean I should do two applications of urea? After applying the urea, can Miracle-Gro still be used when putting in plants? What do I do about an excessive phosphorus reading? It mentions side-dressing, too, but I don’t know what that means.
When fertilizer is applied too early before planting, some nitrogen will be released and wasted. Your soil test instructions mean to apply the fertilizer once, just before planting. It can be raked in; it does not need to be tilled in.
An application of a liquid fertilizer, such as Miracle-Gro, to each vegetable transplant is okay at planting time. It will give it a little boost of immediately available nutrients. Once flowering and fruiting is underway, some “heavy feeder” crops require a mid-season application of fertilizer. Applied on the surface, and watered or gently scratched in, this is known as side-dressing.
You cannot remove excessive nutrients such as phosphorus. Their levels will lower naturally. However, as phosphorus is one of the nutrients destructive to our waterways, do not add phosphorus. We do recommend adding organic matter to your vegetable bed each year, which will reduce the need for supplemental fertilizer.
University of Maryland Extension’s Home and Garden Information Center offers free gardening and pest information at extension.umd.edu/hgic. Click “Ask Maryland’s Gardening Experts” to send questions and photos.