Everyday Gardener // The truth about gardening advice

If you garden even a little bit you know how often you hear advice. Books, magazines, newspapers, bloggers, TV, neighbors — me: Just about everybody’s got something to tell you about gardening, it seems. But here’s the unsettling thing: it’s not all that uncommon to hear stuff that’s wrong or at least debatable.

There are a lot of different reasons why bad and off-base advice abounds. Sometimes, advice that’s wrong or weird becomes an urban legend that gets told over and over as fact. (Use Juicy Fruit gum to get rid of moles.) Occasionally, someone selling something spins advice in a wrong direction to suit their own purposes. (Cover tree wounds with paint or special tree wound goo.) Often, the problem is as simple as the fact that the old advice was good, but it has changed due to new research that isn’t yet widely known. (Plant trees deeply to help them establish strong root systems.)

Whatever the case, it’s always a good idea to question the advice you hear. Ask yourself whether it makes sense, and think about whether you really understand it. (How does raising my mower height to 3 inches help my lawn stay healthy, anyway?) Check out what you’ve been told on the Internet: just be careful to choose good sources of information like your local university extension service. (For us that’s: extension.umn.edu/garden/.)

Blogs can be lame or loony sometimes, as you no doubt know. But there are trustworthy bloggers out there offering valuable advice. A couple of my favorites are Garden Rant (gardenrant.com) and The Garden Professors (sharepoint.cahnrs.wsu.edu/blogs/urbanhort/default.aspx). Garden-related podcasts are also great sources of information. There are several to choose from, but I love “Radio Garden” hosted by Andrew Keys. You can download it, and others, for free at iTunes.

Debatable advice because
it’s needlessly bossy

Even if advice turns out to be sound, you don’t have to take it. One of the things that bugs me the most about gardening advice is that it so bossy and dire. “If you don’t do this your plants will DIE!” This sort of thing scares the crap out of new gardeners and may even keep some people from trying to garden at all. Here’s a good example:

Divide plants only in the spring and fall. It’s true, spring and fall are good times to divide plants because the weather is cooler. Spring is particularly helpful because there’s usually a lot of rain to help roots do well in a new spot. But it’s not like you can’t move plants when these windows of opportunity close. You can move plants whenever you want to as long as you do it at least four weeks before the ground freezes to give roots time to get established.

The key to success when dividing plants at less hospitable times is to provide plenty of TLC.

Keep them well watered. Cut foliage back to about half so the plant’s smaller root system doesn’t have to work so hard to support greenery and blooms. And if it’s really hot and sunny, make some temporary shade for struggling plants by draping a sheet over some chairs.

Bad, wrong and dumb advice

Honestly, I had no idea how much bad, wrong and dumb gardening advice was out there until I started looking more closely at the advice I heard. Here are some examples:

Dress pruning cuts to protect trees from decay and insect pests. This recommendation persists thanks in large part to companies that sell dressing products. Trees don’t really need our help dealing with their wounds. They don’t heal, really. They isolate damaged tissue and “wound wood” eventually develops over an injured area to protect it. Dressing tree wounds keeps wound wood from forming and can actually seal in moisture and cause more harm than the wound every did.     

Top trees to keep them from getting too tall. No. No. No. This is outdated advice that should never be followed. Topping removes a good portion of a tree’s canopy, which not only decreases its ability to photosynthesize, it opens the tree up to all kinds of pests and disease problems and ruins its natural form.

Add nitrogen to soil mulched with wood chips. The myth that wood mulch depletes soil nitrogen persists despite numerous studies to the contrary. Yes, some nitrogen is lost from the top layer of soil as wood chip mulch breaks down, but it’s not enough of a loss to cause a problem in most cases. In fact, research has shown that the decomposition of woody mulch is actually good for the soil because it enriches it with nutrients, including nitrogen over time.

Weird but true advice

Let me just end with this strange recommendation: Use urine as a fertilizer. It may be gross, but you can use urine as a fertilizer because it contains nutrients, mostly nitrogen, that are good for plants. Like dog urine, though, if too much gets concentrated on one spot it can burn plants. So if you want to fertilize with your pee, pour it on your compost pile or dilute it to 1 part urine to 9 parts water and apply it once a week to plants. Be sure you use pee the same day you collect it or it could pick up nasty things while sitting around.  

Meleah Maynard is a writer and Master Gardener. Her first gardening book, “Decoding Gardening Advice: The Science Behind The 100 Most Common Recommendations,” will be published in January by Timber Press.