Mulch, Fertilizer, & Tomatoes

“I dumped quite a bit of redwood mulch on my tomatoes, roses and annuals. The tomatoes are thriving, but the others are just doing so-so. Why the difference and what can I do to improve the condition of the roses and annuals?”
>Jean Karon, Encino
It occurs to me that you may have mulched too heavily around the crowns (where stems or canes meet soil) of your plants. There should be several inches of bare soil between mulch and crowns. If the base of a stem where it touches the ground is covered with mulch, it cannot breathe and growth may be impaired.
Assuming that the mulch is in contact with the crowns, this would not be as much of a problem for the tomatoes.Tomato stems, for example, may be buried several inches in the soil when transplanted and show no ill affects.
Some gardeners even recommend removing the lower leaves of nursery- bought tomato plants prior to setting them deeply in the ground. The reason for this is that roots grow out all along the buried tomato stems, especially from the nodes where leaves were detached, giving the plants more stability and a larger root mass from which to draw minerals and fertilizer.
Annuals and roses are also heavier feeders than tomatoes.
I do not know if you fertilized prior to planting or with what product. Roses must be continually fertilized, as often as once a week throughout the growing season, in order to bloom without interruption. Annuals, unless they are given a generous application of fertilizer at planting, also require constant feeding.
Tomatoes, on the other hand, while they grow best when given a liquid fertilizer boost every two to four weeks (as long as it is low in nitrogen), may produce well enough when fertilized only at planting time, especially when they are planted on a patch of earth where tomatoes have not been recently grown.
Keep in mind that fertilization of mulched plants, except where foliar fertilization is involved, requires raking the mulch to beyond the drip line (canopy or foliage perimeter) of the plant, broadcasting the fertilizer, and raking the mulch back into place.
Crop rotation is not only an issue when contemplating which vegetables to plant in a certain spot from one year to the next.Annual flowers also require rotation. With the aid of fertilizer, you can replenish the minerals that a certain vegetable or annual flower planting removes from the soil.
Fungus diseases are something else again. If you planted petunias along your sunny front walkway last summer, you would be wise to plant something else in that location, such as marigolds, cosmos or zinnias — all members of the daisy family — this summer.
Petunia-loving fungi may build up while petunias are growing and persist in the soil from one year to the next. These fungi would also affect other flowers in the petunia family (Solanaceae), such as nicotiana and million bells (Callibrachoa), even while leaving daisy family members alone.
Inedible figs
“I have two fig trees, `Kadota’ and `Osborne Prolific’ varieties. They bear beautiful figs that are not fit to eat. The trees are around six years old.”
>Harold Tarallo, West Hills
Figs that look good on the outside but are dry on the inside are typically not well-suited to the area where they are planted. `Osborne Prolific’ is a coastal or Northern California fig, while `Kadota’ does best in desert heat. `Kadota’ should ripen successfully in the Valley, however, as long as its soil stays sufficiently moist. A good soaking every third day during the summer is recommended for these trees.
I would also provide both trees with a 4-inch layer of mulch to keep soil moisture steady.
Tree seed troubles
“My neighbor has palm trees in his front and back yard. The trees drop a lot of seeds into our lawn and they are sprouting. Is there anything that will kill the palm sprouts and not kill the grass?”
>Richard Golden, Granada Hills
Thanks to a Web site (, I was able to find what seems like a reasonable two-person solution to this problem.
Kenneth Joergensen recommends that one person “traps” a palm seedling between two pieces of stiff cardboard while the other, using a small brush, paints an herbicide such as Round-Up on the seedling. The cardboard protects the grass from the herbicide.
As a safety measure, it is always a good idea to wear gloves when applying herbicide.
Tip of the week
On the subject of when to plant California natives, fall is often touted as the optimal time to plant. Yet, according to the native plant experts at Las Pilitas Nursery, spring to early summer is a desirable time to plant as well.
To quote from the Web site at, “We’ve normally lost less than 5 percent of our plants planting in spring-summer, even when it is 110 degrees F.”
When planting natives at this time of year, thoroughly soak the area to be planted one week prior to planting and then, following planting, according to Las Pilitas, water your California natives once a week.

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