SIRS BRANCH #1 GARDENING GROUP
August in Your Garden
Revised 7/24/08
Table of Contents
Page #
1 Table of Contents
2 1 Healthy plants require healthy soil:
2 2 Importance of soil air space.
2 3 Soil Compaction-things that produce it
2 4 Soil compaction of lawns
2 5 Soil compaction at 159 Los Robles
2 6 Soil preparation for new plantings
3 7 Plant or Sow Fall and Winter Blooming Annuals
3 8 Summer Bloomers
3 9 Sow Perennials in containers
3 10 Sowing seeds
3 11 Plant Perennials
3 12 Container plants-irrigation
4 13 Plant a shade tree?
4 14 Houseplants
4 15 W Vegetables hen you go on vacation
4 16 Fertilizing & repotting houseplants
5 17 Vegetables
5 18 Irrigation and fertilization
5 19 Fertilization:
6 20 Maintenance: A. Iris, B. shape plants, C. after flowering cut back delphiniums, Shasta daisies,
and yarrows, D. deadheading, E. dahlias and tuberous begonias may need staking, F. prop up
fruit heavy tree branches, G. pick up fallen fruit, H. rake up all fallen leaves, I. prepare beds
for fall planting, J. pruning, K. cut off strawberry runners
6 21 Harvest: A. pears, apples, Soft tomatoes
6 22 Pest control
7 23 New Pesticides
7 24 Insects, etc: A. tobacco budworm. B. lawn moths and grubs, C. spider mites, D. whiteflies,
E. slugs, snails and earwigs, F. aphids on trees
8 25 Lawn problems
8 26. Diseases and potential problems. A. Powdery mildew, B. Fire blight-pears:
8 27 Buying tips for pesticides, and their application
9 28 Fertilizer application through automatic irrigation systems
SIRS BRANCH #1 GARDENING GROUP
AUGUST IN YOUR GARDEN
Revised 7/24/08
For maximum use of this guide, highlight those plants you wish to plant and other chores that need to be done and check them on the table of contents. I have chosen to leave references to older publications in this revised version, and most articles referred to I have on file. These are usually articles that I filed prior to having the capability of scanning them into my computer.
Also, I refer to OSH-Orchard Supply and Hardware frequently, because it is the most convenient garden supply source for me.
1. Healthy plants require healthy soil: Remember, healthy actively growing root tips are the principal source for nutrient and water uptake, they are essential for good plant growth. To maximize this, your soil needs to have a ratio of soil/water/air of about 50 % soil, 25% water and 25% air. This allows good movement of the air into the soil. Remember, root tips denied oxygen for 2-24 hours will die, and the time varies with the time of the year as it relates to the plant’s physiology (active growth, dormancy, etc), plant species and other regulating factors.
2. Major factors that reduce the soil air space: A. Soil compaction is the major cause, and drastically slows the air {oxygen} movement to the root system. .B. to maintain or correct this usually requires an adequate supply of soil organic matter (compost, mulch, etc) which degrades and produces humic acids that in turn create soil aggregates that gives the soil better structure and which can reduce the degree of soil compaction. Nitrogen is essential for the degradation of soil organic matter to produce the humic acids. This emphasizes the value of incorporating organic matter and applying nitrogen in soil preparation for each new planting, for the maintenance of good soil air-space, allowing good soil air movement and water penetration
3. Soil Compaction-things that produce it: A. the winter/spring rains and irrigation, usually do a good job of compacting an otherwise well aerated soil. Compacted soils tend to remain saturated longer after irrigation, again denying the root tips oxygen, as well as favoring root rots. Also compacted soils physically restrict in depth root penetration of the soil and the plant’s ability to forage for its water and nutrient needs. B. Foot traffic: just walking around your yard to pull or hoe weeds or to plant can cause compaction, and the wetter the soil, the greater the compaction. Of course it is necessary to do these chores but choosing where you step, or even placing stepping stones for routes essential for frequent maintenance may be justifiable. Also, surface cultivation following these jobs can greatly minimize the problem.
4. Soil compaction of lawns; this is inevitable and is the primary basis for annual aeration of your lawn. Walking across soggy lawns is a no-no, but even mowing the lawn produces some degree of compaction, and mowing is a necessity.
5. Soil compaction at 159 Los Robles: last year I observed several severely compacted areas in the 2 terraces immediately below the parking strip in front of my house. A dense growth of volunteer Greek poppies had come up from last year’s seed, and was irregularly covering the entire 2 terraces, but they were sparse and stunted in the compacted areas. Growth ranged from 1-2 inches in the most compacted spots, to 12-18 inches high in the non-compacted spots the subsequent intensive winter rains made the compaction worse. In preparation for planting zinnias in these terraces. I attempted spading the relatively dry soil. In the compacted areas, I was unable to penetrate these compacted areas with the shovel, and I resorted to using my hand weeder (tool similar to a large screwdriver with a notch in the blade) to penetrate the 3-5 inch compacted surface soil. I had to use a rubber mallet with the hand weeder to penetrate and break up the surface soil in these dense compacted areas. With this technique I was able to break through the compacted soil. Time only permitted me to work up about ¼ of these 2 beds. The next day my gardener used a spading fork to complete the job. However, even with the spading fork he was only able to penetrate the soil 2-3 inches deep. In retrospect I should have had him use a pick to break through the compaction. However time didn’t allow this.
6. Soil preparation for new plantings: Whenever you plan to put in plants, spread ammonium sulfate (20-0-0) or 16-16-16 (N-P-K, nitrogen-phosphorous-potassium) or similar mixes over the soil surface.
In addition add compost or other similar organic material spread over the surface (note 2B above). I would suggest 16-16-16, be applied no more than once every two years if you have been using it faithfully every year. Instead use only ammonium sulfate-HWL. Remember, N (nitrogen} is essential for plant growth as well as the production of humic acid. Then spade the soil, preferably 1 foot deep, but at least 1 shovel deep. (Note 7 above) ’Failure to do this can result in poor depth of root development and plant growth or even failure to grow, due to compaction and reduced oxygen availability for root tip growth, as indicated above. Plants vary as to optimum conditions, but good soil aeration and proper soil moisture management are always essential for good growth (note 7 above). Also, if you are considering using a slow release fertilizer at or immediately following planting, you may want to reduce the amount of ammonium sulfate you apply before spading. Also, if you want best plants, growth and production ‘double dig’ your soil. (See Sunset’s-Western Garden Book’s-A Practical Guide to Gardening re double digging)
7. Plant or Sow Fall and Winter Blooming Annuals: bachelor buttons (Centaurea cyanus), Calendula officinalis (pot marigold), candytuft (Iberius spp), Iceland poppy (Papaver nudicaule), Nemesia spp, pansy (Viola spp), primrose (Primula spp.), stock (Matthiola spp), snapdragon (Antirrhinum spp), sweet peas (Lathyrus odoratus) [select early bloomer varieties] and Viola spp. It's not too late for a last planting of petunias. Try Goldsmith's hybrid millifora 'Fantasy Pink Morn,' which is a very pale pink, with edges painted a deeper pink, and has a watercolor translucency. It was a 1996 All America Selection winner. It has a natural dwarf habit and does not require pinching. Cosmos are good for borders (check height of varieties), and they are a favorite flower for beneficial insects.
8. Summer Bloomers: It's not too late for some of these and you should find these in your nursery. A few perennials that bloom now and into the fall are Achillea spp. (yarrow), Aster spp., Begonias various types, annual Clarkia spp, includes Godetia spp., Coreopsis spp.*, Cosmos, Dahlia spp., many daylily (some varieties-HemerocalIis spp.), Impatiens spp., Iris ensata, Crinum spp.-Iilies, fortnight lilies (Dietes spp.), geraniums (Pelargonium spp.) Lantana montevidensis, statice (Limoniium perezii), Mexican bush sage (Salvia leucantha) and other Salvia spp., Phlox spp., Portulaca grandiflora (moss rose), Scabiosa caucasica (pincushion flower), Verbena spp., Veronica spp., and Vinca spp. (* I have found Coreopsis an excellent perennial, with a yellow daisy-like flower. It is usually good for 2 or more years if cut back yearly.) For long blooming annuals plant: Celosia argentea (cockscomb), Cosmos spp., annual lobelia (Lobelia erinus), Madagascar periwinkle (Vinca rosea), French or dwarf African marigolds (Tagetes spp.), Nemophila spp., petunias, annual phlox (Phlox drummondii), sunflower (Helianthus spp.), sweet allysum (Lobularia maritima), and Zinnia spp.
9. Sow Perennials in containers. For bloom next spring and summer, sow Aster spp. basket of gold (Aurinia saxatilis), carnations (Dianthus carophyllus), columbine (Aquilegia spp), Coreopsis spp., Delphinium spp., Dianthus spp., feverfew (Chrysanthemum parthenium), Gaillardia spp., Geum spp., Heuchera spp. (coral bells), hollyhock (Alcea rosea), Iceland and oriental poppies (Papver nudicaule & P. orientale), Lupine spp., Pentagon spp., Phlox spp., primroses (Primula spp.), purple coneflower (Echinnnacea), Shasta daisy (Chrysanthemum maximum), statice (Limonium spp.), Viola spp., wallflower (Erysimum chein) and yarrow (Achillea spp.).
10. Sowing seeds: After my greenhouse was constructed, Helga and I planted a variety of seeds in flats of potting mix. The seed germinated well, but the labor required to separate the seedlings and transplant them into clean 6-packs was very time consuming, and the transplants didn’t approach the quality of those we could purchase in the nursery. We decided that we would only do this for plants and varieties we wanted and couldn’t obtain in the nursery. On the other hand we found direct seeding of radishes, carrots, sweet peas, and a few others in the garden were very practical.
11. Plant Perennials: Chrysanthemums, geraniums, 'dusty miller'(actually a variety of plants with gray foliage), fuchsias-plant uprights and hanging baskets; bulbs- Colchicum corms (autumn crocus), Lycoris (spider lily), Nerine, Sternbergia and Zephyranthes (Zephyr flower) are recommended by Sunset, also clivia and watsonia, bearded iris. If you want humming birds, plant red, pink and funnel-shaped flowers such as abutilon, fuchsias, honeysuckle and red trumpet vine.
12. Container plants-irrigation: The frequency of irrigation is somewhat dependent upon the specific plant. However, the degree of exposure to the sun, the type of pot or container, the type of potting mix and amount, exposure to wind, whether on a deck or a hanging basket, all can affect the frequency of irrigation required. Plastic pots and containers, dry out more slowly than clay pots, and usually result in a somewhat warmer soil that favors the growth of most plants. However, some plants do best when their roots are kept cooler. These might be expected to do better in clay pots, because moisture evaporating through the clay should cool the pot slightly. In most cases during the summer months, most containers require watering every day or two. Some even twice a day (hanging pots and especially baskets). In most cases, it is usually best to apply sufficient water, to have about 5% drain out of the bottom of the container. This assures you that the water has reached the bottom, and it avoids the buildup of salts in the surface soil. Any time salting-out (whitish surface soil) does occur on the surface, place the pot(s) in the sink and slowly apply sufficient water over the plants to leach out these salts. Unless you are home all or most of the time, an automatic irrigation system is usually needed to maintain healthy plants. As I always say “a green thumb” is usually 95% proper water management. Also, like all irrigation practices, the more water used, the more fertilizer is needed if you want maximum growth. All of this results in a better growth and appearance of your plants.
13. Plant a shade tree? Some suggestions-Chinese hackberry (Celtis sinensis), Chinese pistache (Pistacia chinensis), Japanese pagoda tree Sophora japonica, 'Raywood ash (Fraxinus- Raymond??) or red oak (Quercus rubra). (Sunset- August 1998, p60).
14. Houseplants: In general, foliage plants can tolerate the least light, whereas most flowering plants require indirect sunlight and should be placed close to windows that face the sun for several hours a day, for maximum blooming. Some examples are your indoor orchids, Christmas cactus, African violets. A few will tolerate direct sunlight, but most tend to sunburn from direct sun. Leaf burn looks like concentric spots in the center of the leaves. Do not get leaf burn confused with tip burn which is usually caused by salt build up or over fertilizing and shows up in the tips of the leaves. Some of the better plant choices for high light areas are Arbicola, Ficus Benjamina variagata, Phoenix robellini, Dracaena massangeana, Philodendron and pothos. However, I have found that my Ficus Benjamina does well in darker areas as well. As you well know, Ficus Benjamina does not like drafts or to be moved, but requires some indirect sunlight otherwise it will usually result in it shedding considerable foliage. Also if you don’t want a lot of growth, I found that if I didn’t fertilize the plant it stayed green, and grew slowly. However if the new growth begins to show a slight yellowing, it is probably time to add a little house-plant fertilizer to the water.
15. When you go on vacation, pull your potted plants out of hot spots so they won’t dry out as quickly. Don’t leave plants in buckets of water as the lack of oxygen will kill off the root tips, and if they are quite subject to water molds and these are present, these too can kill the plant. However you can help the plants by filling trays or saucers with pebbles and water, and then placing them on the pebbles. You may also have spots to place them outside, where automatic irrigation can be made available. However, anytime you move a houseplant outdoors, it is usually a good idea to place it in a somewhat shaded spot for several days to weeks, before putting it out in direct sunlight. Most plants do best with a distinct watering and fertilizing schedule. Light weight potting mixes allow the soil to aerate better and that is why they are used by plant production nurseries. However, they will usually hold the least soil moisture, and require more frequent watering. During the past year there have been many new potting mixes that have a product in the mixture that holds water and releases it to the roots. My single and current experience with a potted begonia we received as a gift has not performed well, and I assumed it contained such a product. However there are several things I don’t know about its make up. In any case, your own experiences will usually give you the best guidelines for scheduling your watering. If you use the 'double saucer' system (outer saucer to catch overflow) for watering your house plants watch the differences in time required for all of the water to sub-up into the pots. Those that suck up the water in the shortest time period are likely those that require the most frequent watering. In general, the frequency for irrigation ranges from twice a week, to once every 2 weeks. The warmer the room, the more frequent the need for re-watering. Usually it is not a good idea to fertilize just before you go on vacation, as new growth may require an increase in its water needs. This applies to both indoor and outdoor plants not on an automatic irrigation system.
16. Fertilizing & repotting houseplants can sometimes be the most challenging. Their needs can vary extensively. Blooming house plants require a proper fertilization to bloom well. After blooming, most house plants require fertilizing with a higher N percentage to encourage growth, but as they approach their blooming period, the N percentage should be reduced substantially and the percentage P increased. Also, with foliage houseplants, if you don’t want them to increase in size, many will do well for months without applying any fertilizer. Also, it is recommended that most house plants be re-potted every year or two, but if you are satisfied with the way yours are growing, don’t bother until they appear to need it...
17. Vegetables (applicable to a normal summer, some of the more cool-tolerant vegetables are in bold print [SF Chron.7/21/98]): It's not too late to sow directly into the ground, beets, broccoli, carrots, cauliflower, chard, Chinese cabbage, kale, lettuce, peas, radishes, spinach and sweet corn (if planted early). Sow in containers for transplanting, broccoli, Brussel sprouts, cabbage, cauliflower, chard, lettuce and spinach. Continue to pick vegetables, whether you use them or not. The plants will stop producing if not picked. Toward the end of the month, pinch off the last few blossoms on the ends of eggplants, peppers, melons, squashes and tomatoes so energy will be spent maturing fruit that's already set. Herbs: rosemary, basil, chives and other herbs. Mature, woody and spreading herbs can be propagated by dividing the plant and using the new outer shoots.
18. Irrigation and fertilization: As you increase watering. You should also increase fertilization (slow release fertilizers can compensate for this). August and September are normally the hottest months and as such require maximum water usage and fertilization. Particularly watch camellias, a water shortage now can mean an excessive drop of dead, brown buds next winter when the plants are in bloom. Also watch azaleas, rhododendrons, chrysanthemums, roses, fuchsias and flowers. With lawns, if foot prints remain after you walk on your lawn, it needs water. Shrubs, trees, especially fruit trees and other plants with good taproots may need a deep irrigation if they can root deeply in your soil. You may need to make basins around the drip line of each tree or plant to spread the water more evenly. Watch hydrangeas and keep them well watered during hot spells. If plants are watered by an automatic system, make sure that it's running often enough and long enough to water plants adequately (area & depth). Check soil moisture by digging down to about a foot with a trowel, better yet use a moisture probe that will register moisture down 6-8 inches, or even better use both methods. Water and feed cane berries and strawberries for a better fruit set next spring. Keep bougainvilleas on the dry side during blooming season for brighter brackets (blossoms). Watch outdoor vigorously growing potted plants; they may require watering twice a day. In the hot weather, they usually need to be watered at least daily. Exceptions being the much larger pots with considerable more soil in which to retain moisture and a deeper more extensive root system. Mulching the soil surface, where practical, will conserve soil moisture and allow the development of shallower surface roots, particularly beneficial for shallow rooted plants. Water newly planted citrus trees twice a week in normal summer weather, established trees at least every other week. Again, during hot spells, water more frequently.
19. Fertilization: Most plants that are actively growing need to be fertilized at least once a month with a high N (nitrogen) fertilizer. Where practical, you may choose to frequently spray a Miracle-Gro All Purpose formulation, as you see it frequently advertised on TV. This is especially true with blooming plants and will produce a rapid response, but usually should be followed with additional applications. Where a controlled release fertilizer has been used, you may choose to use some additional ammonium sulfate. A. Potted plants requiring frequent watering and to which a controlled release fertilizer has been applied may even do better if additional fertilizer is applied twice a month. B. Tomatoes, roses, lawns and most others will need fertilizing, again unless a controlled release Osmocote type fertilizer has been used. (Sunset-August '98, p60) states the following: C. Most rhododendrons will be setting flower buds, feed these with a high P (phosphorous) fertilizer. D. Cymbidium orchids should continue to be fertilized every 10 days or 2 weeks with Grow More’s red orchid formula (NPK 30-10-10), or I would suggest you use Miracle-Gro’s All Purpose fertilizer (NPK 24-8-16), which although not exactly the same is near enough, considerably less expensive and one you should have on hand for many other uses. Next month- September through February shift to Grow More’s blue Bloom Formula 6-30-30 to initiate flower spikes or a similar cymbidium fertilizer from Rod McLellan’s if you still have some on hand... If you don’t have either of these latter two, but you have Miracle-Gro 9-18-9, I would suggest that you use that even though different. Again, it is less expensive. You may want to check your nursery supply for Gro More’s other 3 orchid fertilizers. Compare their prices per pound for each product. Use Gro More’s yellow formulated Premium Orchid Food 20-20-20 for your cattleya’s, vandas, dendrobiums and other orchids year round. E. With houseplants you may use an Osmocote controlled release fertilizer. or a Schultz house plant type fertilizer, fertilizer spikes or other houseplant food. Check for nutrient deficiencies-yellow leaves usually indicate that plants are short on nitrogen N, but if the leaves are yellow and veins are green they may need a chelated iron or other micronutrient. Spray with something like the standard Miracle-Gro 9-18-9 containing micronutrients.
20. Maintenance: A. Iris-2 recommendations: divide iris rhizomes every 2-4 years or many types will pretty much stop blooming (SF Chronicle 6/03/02). Divide crowded bearded iris and they should produce more flowers next spring... B. shape plants (light summer pruning), C. after flowering cut back delphiniums, Shasta daisies, and yarrows, D. keep blooms coming by removing (deadheading)mature faded flowers which may be developing seed pods. This is particularly useful for cosmos, coreopsis, marigolds, zinnias, and of course roses. E. dahlias and tuberous begonias may need staking, F. prop up fruit heavy tree branches so they won't break .G. pick up fallen fruit, H. rake up all fallen leaves to prevent disease and discourage insects. I. prepare beds for fall planting (again, be sure to incorporate a fertilizer and compost or other organic matter). J. Don Burns, San Mateo Co. Times, 7/11/98 stated that trimming camellias now will result in significant reduction in flowers next spring. He recommends pruning only where limbs are rubbing against something. However, if you are trying to control height, you may want to ‘top’ the plant. K. cut off strawberry runners before they root to avoid a tangled mass of plants. L Once yarrows have finished flowering, remove the faded flower heads and stems down to the second set of leaves. M. ripening fruits, such as melons, and tomatoes, in contact with the ground may be placed on an inverted aluminum pie tin to avoid rots, soil insects and even gophers. The stems of certain melons when ripe come off easily. N. lawns: now is the time to raise your cutting height on your lawn mower to 2-2½” high. Mowing higher prevents the soil from drying out. Also, when walking across your lawn, turn around and look at your footprints, if they show it means your lawn is dry. Also watch your lawn for areas where the grass remains approximately the same size and is turning light yellow, water may not be adequately penetrating these areas. If you have a soil aerator, it would be well to use it on these spots to improve water infiltration and soil aeration. If the whole lawn appears to need perforating, it is usually better to have an experienced dethatch and perforate your lawn. Also see pest and disease control below.
21. Harvest: A. pears, the former method for harvesting pears when green ripe was to lift the pear to a horizontal position, and if the stem frees itself from the fruit spurs it is ready. If it doesn’t leave the pear on the tree until it does (this applies to picking both pears & apples). However today, most pears in the market are green or yellow green, and are excellent tasting Bartlett pears from California, Argentina, Chile and New Zealand that are much greener than formerly recommended for harvest. B. tomatoes are usually best for flavor when they have first turned red, and their harvest will also favor better development of remaining fruit. However some may still prefer the completely vine-ripened fruit. Search plants thoroughly and don't miss the ripe ones. Soft tomatoes can harbor harmful bacteria that can grow in canned tomatoes.
22. Pest control: During the rainy winter period, many insects can be suppressed, while others reproduce more extensively. However with the extensive development of weeds in your neighborhood, certain insects could be having a field day and building up to high populations. It is hard to predict. Weather plays an important role in what are our predominant pests and diseases. The amount of rain, its frequency, temperatures, microclimates and specific plants in your yard, etc. all can have a direct effect on the problem pests and organisms as well as affecting the populations of their predators, parasites, competitors, etc. The following is taken from the California Cotton Review, June 2004 and elaborates on the subject. “Cotton insects are influenced by rainfall and temperature. Rainfall and its pattern of distribution across the San Joaquin Valley as well as the timing of occurrence determine plant composition and duration of plants in the landscape. Temperature regulates the rate at which insects develop and reproduce as well as the duration of plant hosts. The more heat, the faster generations turn over, but also the faster host plants utilize available moisture. Insect population densities that threaten cotton depend on the optimal balance between these two factors. Enough rainfall must fall to allow good development and distribution of weedy hosts and enough heat must be available to allow insects to turn over generations in the shortest possible time. Since the San Joaquin Valley is located in a Mediterranean climate, the probability of rainfall is almost nonexistent after May. Thus, any insects found on weed hosts outside cultivated areas will be required to move into crops or face starvation. This movement is determined by the factors mentioned before, rainfall and temperature. In years when hosts are available and temperatures are adequate, multiple generations can develop and higher densities of pests can move into cultivated areas later in the season. In years when rainfall is limiting, plant hosts may dry up and force movement within the first generation and before cotton is susceptible to damage. Predicting pest pressure caused by a complex of insect pests is a fool’s errand. However, experience gained over several decades and collaboration with many seasoned pest control advisors and growers allow us to interpret and extrapolate a rational estimate of insect pressure.”
23. New Pesticides: Neem oil is a relatively new product that has been around a few years. It appears to be a good pesticide. As a miticide it kills all stages, but as a fungicide, the oily film on the leaves excludes fungal spores from penetrating the new foliage. Foliar fungicides protect the new clean leaves as a result of a coating of the fungicide. However, in the case of systemic fungicides, they are absorbed by the leaves and systemically distribute themselves throughout the plant and prevent the development of the fungus. Their concentration within the leaf is reduced by expanding new growth and slow degradation.
24. Insects, etc: A. a major pest at this time on petunias, the common red geranium and a few other flowers is likely to be the tobacco budworm. It feeds on the young flower buds and leaves and deposits its droppings on the foliage. There are several materials to use, but probably the best is designated BT (Bacillus thuringiensis) which is a bacterium that induces a disease, somewhat specific to worms, such as budworms. Companies producing it continue to isolate, culture and incorporate new strains into this unique insecticide, expanding the control of many different worm species. Being rather specific to worms, it shouldn’t kill most beneficial insects. B. lawn moths and grubs can be a problem at this time. Lawn moths (sod webworms) are actually several different moths with similar habits. They fly around at night and drop their eggs as they fly. The only insecticide which I am aware of for such is Ortho’s Bug-B-Gone Multi-Purpose, Insect Killer-Ready Spray but I have no personal experience or knowledge of its effectiveness. As for grubs, Ortho has Bug-B-Gone Multi-Purpose Insect Killer Granules. I would suggest that your check with your reputable nurserymen to see what they recommend. C. spider mites produce webbing on plants and a summer oil spray should control the eggs. Many insecticides will kill the adults but not the eggs, thus the value of oil. Neem oil should be very effective against spider mites. However, there are other products available One such product is Bayer’s 2-in-1 Systemic Rose & Flower care, it has the systemic insecticide disulfoton, impregnated on fertilizer granules. D. whiteflies can be a problem, but conventional insecticides recommended usually require frequent re-treatments. Again Bayer’s 2-in-1 Systemic Rose & Flower care, and Bayer’s All-in One Rose & Flower Care, a liquid drench formulation containing the systemic insecticide imidacloprid have whiteflies listed as being controlled. You might want to try the somewhat effective sticky whitefly traps, but if not be available in your nursery, you might try the similar sticky tape fly traps. E. slugs, snails and earwigs can be a problem. There is a relatively new product on the market, iron phosphate snail and slug bait. It is non-toxic to pets -and humans. I don’t know how effective it is, as I have not used it. There are many baits and liquid squirts which contain metaldehyde for snails and slugs, and there is Sevin and several baits for earwigs. All 3 insects can defoliate young seedlings, immediately after transplanting. They hide during the sunlight hours under vegetation, and then come out at night and feed extensively. With snails and slugs, their slime trails identify their daytime habitat, baiting these is usually quite effective. F. aphids on trees: aphids excrete large quantities of a sugary solution called honeydew, which may coat plants beneath a tree or shrub. Soon a sooty mold fungus usually develops on the honeydew, causing the bark, branches and leaves to appear black and dirty. Ants feed on the sticky substance. Cars parked under such trees can be covered with the honeydew, and the honey-dew can damage the finish of newly painted cars. It is likely to be a problem where lacquer type paint is used, and not a baked enamel type. Again, the relative new Bayer product Tree & Shrub Insect Control is worth trying.
25. Lawn problems: Insects, diseases, and a broad variety of problems can produce a variety of somewhat similar and easily misdiagnosed problems. Control and/or correction can be quite different. If you have problems with your lawn, I would suggest you look at pictures and descriptions on pages 64-77 of Ortho’s Home Gardener’s Problem Solver after the meeting.
26. Diseases and potential problems. A. Powdery mildew is extremely damaging to tuberous begonias and many other plants such as roses. However, control requires multiple treatments. The Bayer product Disease Control for Roses, Flowers & Shrubs applied as a spray deserves being tried. However if you have soil fungi attacking the roots and tubers of begonias and other plants. I would suggest you try Bayer’s All in One soil drench. B. Fire blight-pears: Infection on my pear tree has usually occurred on the late bloom, which I prune back at least 6 inches beyond the discolored bark. The infection results from bees and other pollinators pollinating the 'late bloom' after they have pollinated a neighbor's infected blooms. If you have this, cut back 6-12" below the blackened tissue. Dip your pruners in a dilute bleach solution between cuttings to avoid transmitting the disease. When finished dry the pruners carefully and oil them to prevent corrosion of the pruners. Failure to stop the infection can in some cases result in the tree dying. My pear tree may be destined for possible death, because the disease got away from me 3 years ago. It had 2 severe infections, which required cutting out 2 medium sized limbs, but it is still holding its own.
27. Buying tips for pesticides, and their application: When buying pesticides, most similar formulations of a specific pesticide or fertilizer are usually quite similar and usually can be used interchangeably and as such you don't need 3 containers of the same active ingredient. However, compare the percentage of the active ingredient (usually the first chemical listed) and if one formulation has a much higher percentage it will usually be less expensive per unit of active ingredient and you can apply the same amount of chemical at a proportionally reduced rate. The same applies to fertilizers. Minor variations in the percentages of N, P and K (nitrogen, phosphorous, and potassium) usually don’t justify having one for vegetables, one for roses, one for camellias, etc. With the exception of ammonium sulfate, usually the least expensive fertilizers are the all purpose NPK's, 10-10-10, 16-16-16, etc. Ammonium sulfate is usually a substantially less expensive fertilizer and usually can be used more extensively than most. It contains N only (actually it does have S-sulfur a secondary nutrient needed in amounts similar to NPK). In most situations, N is used by or leached from the root system more extensively than the P and K. As such it frequently can be substituted for the more expensive mixes. I probably use ammonium sulfate about 3 times out of every 4 applications of fertilizer that I apply. Ammonium sulfate is a completely water soluble fertilizer, and the least expensive. For the average lawn, only occasionally do you need to apply a lawn fertilizer containing more than just N. Ammonium sulfate (N) can be spread by hand, or with a spreader, or dissolved in water and applied using a hose proportioned (siphon). OSH no longer carries the hose siphon, but I will check at Lowe’s and Home Depot. On lawns I prefer to use a hose proportioned. With this, you check the label to determine the amount of fertilizer needed based on square footage of your lawn. Then dissolve the ammonium sulfate in a bucket of water, attach the hose proportioner to your faucet, drop the tube into the bucket, attach a fan nozzle to the end of the hose, turn on the faucet full force and walk back and forth over the lawn spraying until the bucket is empty. Then add just water to the bucket to rinse the fertilizer from the hose proportioner, because the fertilizer can corrode the unit. Then disconnect the hose-siphon, and repeat the process using just water to wash the fertilizer off of the foliage to avoid burn. Also you need to do this when you are spreading a dry fertilizer to avoid burning the foliage. However, in most cases, you probably have a sprinkler system which you can turn on to do the same.
28. Fertilizer application through automatic irrigation systems: One of the best and easiest ways to apply a water soluble fertilizer is to insert a unit in the irrigation line in a convenient location beyond the solenoid valve. I use 2 types, a line strainer from which the base can be unscrewed and a water soluble fertilizer added. Again OSH has discontinued stocking this item, probably because it didn’t move well, but they are available elsewhere. However, more frequently I use a less expensive type that I fabricate myself and find more easy to use. I make them from ¾ inch PVC and standard PVC fittings with pipe thread and hose threaded couplings. (I will circulate such a unit during the meeting).