Q: What variety of avocado is best? I don't want one that produces fruit only every other year, such as a 'Fuerte.' -- L.K., Montebello A: 'Hass,' 'Bacon' and 'Zutano' are the varieties that top my list. Unfortunately, almost all avocado varieties have the habit of bearing heavily in alternate years, but certain ones exhibit the trait more than others. The 'Fuerte' is notorious in this respect. Climatic conditions can also affect a tree's fruit bearing. A hot spell immediately after fruit set can result in the dropping of almost all of that year's crop. Conversely, cool weather during a bloom period can reduce fruit set. If an avocado tree fails to bear for two seasons in a row, it is probably a poor variety for its particular location and should be replaced.
Q: Is it true that bromeliads can grow without soil? Also, how do they do indoors? --N.B., Long Beach A: Bromeliads have always been viewed as somewhat distinctive members of the plant kingdom. They depend on humid air--not damp soil--to obtain their necessary moisture. Since each genus, and even each species, varies in its needs, it is difficult to generalize about suitability to an indoor environment. Cryptanthus is a terrestrial genus that performs nicely indoors. A soil mix serves both as a medium to anchor the plant and as a reservoir of moisture to enhance humidity around it. Although many bromeliads are grown and appreciated exclusively for their colorful foliage, other types have blossoms that are most spectacular. If plants don't bloom, it is usually the result of too little light--as with many other flowering plants. Direct sunlight, however, is never recommended. Scale insects and mealybugs are the most common pests of bromeliads. Diazinon or Malathion will provide control but should be applied only as recommended on the label.
Q: The potted-plant mixes on the market get very expensive if you have a number of large pots. Can I mix up my own?--L.V., Encino A: A general-purpose mixture for growing most bedding plants or ornamentals that benefit from organic matter should include five parts good loamy garden soil, four parts organic matter and two parts sand. Loam is soil that is about equal parts clay and sandy silt. Heavy clay soils or very sandy soils are not as suitable. The organic matter can be peat moss, well-rotted manure, decomposed leaf mold or compost. If the original soil is on the heavy side--or when camellias, azaleas or succulents are involved--a mixture of one part garden soil, one part organic matter and one part sand is recommended. Using a mixture of sand and organic matter eliminates water-caused salinity problems. Such mixes are easily leached, making it possible to flush out salts with normal watering.
Q: Many visitors to Hawaii are enchanted by the wood rose since it looks like a beautiful bit of wood carving. Would it survive in Southern California?--V.G., Torrance A: The wood rose--a member of the morning-glory family--grows throughout the tropics and is a popular plant novelty. Since it spreads rampantly and often covers buildings, fences and trees, it is considered a pest by some. I doubt that it will grow here, unless it is in a greenhouse.
Q: Does the flowering of the prayer plant mean that it is in trouble?--D.B., Pasadena A: Although many exclusively vegetative indoor plants have been known to break into bloom when under stress, such is not the case with a prayer plant (Maranta leuconeura ). A mature plant will flower when it is culturally satisfied. Such activity is a sign that its owner is doing a good job. The prayer plant never seems to pose any problems, provided that it gets plenty of light. Remember that many indoor decorative plants have a resting period in the fall and winter months, even though they look no different than they do the rest of the year. During the fall, gradually cut back on watering, checking for soil moisture by touch, and discontinue feeding.
Q: How long can we store weedkiller before it loses its potency?--A.K., Redlands A: A herbicide stored in a dry, airy place has a shelf life of between two and three years. Keep it well sealed in its original container.