Question: Is it OK to use eucalyptus mulch around tomato, squash and pepper plants, or will it affect the taste of the veggies? I have heard that it helps keep insects away.
Answer: It's OK, but native cedar mulch is far superior. It is cheaper, repels pest insects better and breaks down better than eucalyptus.
The only exception is if you live where eucalyptus is growing. It's best to use mulch made from plants growing on your property.
Question: I have several small beds around the front and sides of my house for color. I have been organic for more than five years.
All the beds face the mid- and late-day sun except for a couple that are partially shaded by trees. I like periwinkles for color and have planted them for the last three or four years. I have three beds on the south and southwest where the periwinkles will not grow. Until this year, about 50 percent died, and sometimes a replanting also would die. I planted periwinkles about three weeks ago, and all of the plants in these beds are dying. The other beds are fine.
I prepare the soil by adding rock powders, compost and cornmeal. Is there something I can do to cure this problem?
Answer: Yes, but you can't do it in those beds. Periwinkles must be grown in full sun all day, and morning sun is the most important sunshine of the day for plants.
Your amendments are fine, but another culprit is the cool weather we have had this year. Periwinkles need warm soil, hot weather, full sun and biologically active soil.
They also do much better if grown from seed so that they are not exposed to the synthetic products used by most growers.
Question: The leaves on my oak tree are not green; they are a greenish yellow. The tips of the leaves look like they have been burned, but I know they are not. My house faces west, and this is a young tree, maybe 6 to 7 feet tall.
Answer: There are many yellowing trees around nowadays, and many of them are red oaks.
First, the tree could be a cross between a pin oak and a red oak. If that is the case, replacing the tree is the only solution because pin oaks are not suited for growing in the alkaline, clay soils of the Dallas area; they need acid, sandy soil.
The off-color also can result from the use of synthetic fertilizers.
An even more common culprit is "weed and feed" fertilizers or other herbicides. In this case, detoxify the soil with Norit activated carbon or zeolite followed by my Sick Tree Treatment.