Master gardener Paul James shatters a few gardening myths, plus offers a few tips and tricks:
Cooking Soil
Have you ever heard the suggestion that you should sterilize potting soil in the oven? Cooking potting soil in the oven for a half hour around 180 degrees has long been recommended as a means of sterilizing or pasteurizing the soil to eliminate fungi and bacterial diseases that may be lurking in it. But have you ever smelled cooked dirt? The stench is awful, and it's one of those smells that sticks to the curtains and lingers for days. If you're concerned about contaminated potting soil, either sterilize it by pouring almost-boiling water over it, or add a little compost to it, which is full of disease-fighting microbes. You can also buy a package that has already been sterilized.
Pesticide Bloopers
A fairly common gardening practice that falls under the heading of "I Wouldn't Do That If I Were You" is to routinely douse plants with pesticides even when there aren't any pests in sight. Pesticides should never be used as preventive sprays, especially the broad-spectrum products that claim to kill anything that moves. In fact, they shouldn't necessarily be used when only a few pests attack your plants. A little damage isn't likely to spell disaster for the plant, but more important, if you spray pesticides all over, you'll wind up killing both the good and the bad bugs. If given the chance, good bugs do a fine job of keeping the bad bugs in check.
Not all pesticides are alike, whether organic or synthetic. For instance, some pesticides are contact poisons, meaning you must actually hit the bug in order to kill it. Others must be ingested, so the bug has to eat a leaf that's been sprayed with that type of poison for it to work. It is essential that you know the difference. Otherwise, you may spray all day and still have bug problems. It's also essential that you use the right pesticide for the particular pest you're trying to control. A number of products are available that target specific types of bugs without harming others.
Preventive spraying is the key to combating fungal diseases, because once a fungal disease surfaces, there's little you can do to get rid of it. For plants prone to such diseases, begin spraying in early spring just as new growth emerges and continue spraying about every 10 days. Stick with conventional products when it comes to herbicides, and don't use kerosene or gasoline. Both will kill weeds and contaminate the soil for years, and they're far more dangerous than most herbicides on the market.
Overfeeding
There's no denying that most plants will benefit from a little fertilizer now and then, but most homeowners apply far more fertilizer than plants actually need. Those are often the same homeowners who complain about pest and disease problems. Why is that? Overfertilization, especially with products high in nitrogen, produces an abundance of tender, succulent growth, which is what bugs enjoy munching on most. Overfertilizing late in the season can create another problem that no spray can prevent: freeze damage. If you fertilize certain plants, especially shrubs, while it's still warm out but also at a time when freezes are just around the corner, the new growth won't have a chance to harden off and prepare itself for sudden temperature changes. The entire plant rarely suffers, but the tips will turn brown and make the plant look bad.
Winter-only Pruning
Another gardening myth is the notion that fruit trees should be pruned only while they're dormant. Summer is the ideal time to remove watersprouts that shoot up from the main limbs. It's also a good time to make selective cuts near the ends of branches and thinning cuts to open up the tree a bit. Remember to practice good sanitation when pruning fruit trees because it's easy to transmit a disease from one tree to another with contaminated pruning tools. The best way to prevent the spread is to dip your tools in a mild solution of bleach and water between each pruning cut.
)
