Volume 2, Issue 4         July 2004         Steven Jay Porus, Publisher         sjporus@unlaccess.com

• Designing a Historical Iris Garden
• Citrus Fruit Selection
• Implementation by a New Breed of Landscape Contractor
• Plant Disease Maintenance
• LandsExpo Update

Preserving a Little of the Past

BY SUSAN SIMS, Sims Tree Learning Center

The Fleur-de-lis embraced by the French monarchy in history utilized the stylized iris. The iris is made up of multiples of three (3 standards, 3 falls ...) symbolizing the trinity of father, son and the Holy Ghost. Then as now everyone going to war wants god on their side. Remember more recently when sugar packets had an Iris on them? An old iris variety, Iris germanica variety Florentina, was used heavily as a medicine or potion, fixative and enhancer of color and fragrance, despite the fact some have allergic reactions and iris are generally considered poisonous.

We at the Sims Tree Learning Center have collected over 47 varieties of Historic iris. The oldest iris is probably Iris germanica described about 1600. For those unfamiliar with how iris grow each iris blooms once then reproduces by sending out daughter or new rhizomes from the mother rhizome. The irises in the Tree Learning Center garden are direct, non-sexual descendents of the original iris found or hybridized in the year found on their label.

These irises are clean and simple compared to today's very fancy tall bearded iris with flounces, spoons, ruffles, variegations and other adornments. Today's iris do have a lot to offer including rebloomers, however visitors almost always give us a WOW when walking by our historic iris collection. All our irises are clearly labeled with their name and date and planted chronologically. The oldest dated varietal iris in our collection is Swerti from 1612, and the youngest member of our historic collection is Indian Chief, 1929. The Historic Iris Preservation Society or HIPS considers anything over 30 years old as being historic. Since that makes me historic I have a hard time sharing their view of what's historic. Those irises newer than 1929 can be found in Sims' regular iris collection.

Sims Tree Learning Center sells some of our excess rhizomes and the Historic Iris Preservation Society periodically offers rhizomes for sale. You can visit The Learning center in spring to view these treasures or visit anytime online at http://www.simstlc.com If interested you can join HIPS by contacting Mary Forte, 9320 Lakota Way, Atascadero, CA 93422 jforte@aol.com Annual membership cost $5.00.

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Selection of Citrus Fruits: Oranges, Lemons, Limes, Grapefruit, and Mandarins

BY DONALD R. HODEL, Environmental Horticulturist, UCCE

Some of our most popular fruits, including oranges, lemons, limes, grapefruit, and mandarin oranges (tangerines), can be easily grown and enjoyed fresh off the tree in our home gardens with just a little attention to selection, planting, and care. Also, citrus do double duty as attractive ornamentals, and are highly valued for their handsome, evergreen foliage, fragrant flowers, and decorative fruits. Here are some points to consider when selecting and planting citrus trees for your garden.

Heat and Cold Requirements

Lemons and limes need the least heat to ripen but are the most sensitive to cold and frost; thus, they perform best in coastal areas. Oranges and mandarins need more heat and are more tolerant of cold and frost, so they perform best in the interior valleys. Grapefruit need prolonged, high heat but are sensitive to cold and frost; they perform best in the low desert. Varieties

Numerous varieties of citrus trees are available that have been selected and propagated or cloned for one or more desirable traits, such as pest and disease resistance, cold hardiness, harvest time, flavor, and ornamental value. These varieties or clones are grafted or budded onto a rootstock that has also been selected for a particular trait, usually disease resistance, cold hardiness, or size control. Chance trees resulting from seeds rarely produce good quality trees or fruits, so it is important to choose named varieties (clones) that have the characters you desire.

Some Citrus Varieties

Grapefruits-'Duncan', 'Marsh', 'Redblush', 'Ruby'. Fruits ripen Nov.-March in desert, Feb.-Nov. in cooler areas. The seedless, white-fleshed hybrids 'Oroblanco' or 'Melogold' are much better adapted to and perform well in cooler areas like the coastal regions and inland valleys. Their fruits ripen Nov.-April.

Oranges-'Robertson Navel'. Fruits seedless, ripen Nov.-May; more heat resistant than 'Washington Navel'. 'Washington Navel'. Fruits seedless, ripen Jan.-May; not adapted to desert. 'Valencia'. Fruits with seeds, ripens after navels, April-Aug. in cooler areas, Feb.-May in desert.

Limes-'Bearss (Persian or Tahitian). Large fruited, ripen Aug.-May; low heat requirements; more frost tolerant. 'Mexican'. The lime of bartenders; high heat requirements, very frost sensitive, not recommended for California.

Mandarins-'Satsuma'. Fruits easy to peel, sweet, juicy, seedless, ripen Nov.-April; fairly cold hardy; not good in desert.

Size of Mature Trees

Citrus trees need much light, so select a site that will receive sun all day. Avoid planting under or next to larger trees, houses, and other structures that will block sun light. Citrus are not too particular about soil as long as it drains well and does not remain soggy or wet. Plant cold-sensitive varieties or those with high heat requirements on the south side of a home, building, wall, or other structure that can block cold winds but trap and collect heat during the day and radiate it at night. Avoid planting citrus in windy areas or in low spots, such as at the bottom of a hill, where cold air drains and collects at night. Citrus often do not perform well in lawns because of differing water needs.

Planting

Planting citrus trees does not differ too much from planting other trees and shrubs. See the Garden Information Series brochure about selecting, planting, and caring for trees for information about how to plant container-grown citrus trees. Citrus roots are unusually sensitive to disturbance and deep planting so take care to keep the root ball intact and position it 1/2 to 1 inch above the soil line. Water newly planted citrus trees well because they are sensitive to drying out. Mulch with a three-inch layer of compost. See the Garden Information Series brochure about composting and mulch for additional information. Spring is the best time to plant citrus in coastal areas and intermediate valleys but wait until fall to plant in the desert.

Watering

Citrus trees need regular water to grow, develop, flower, and fruit adequately. Apply enough water each time to moisten the soil to about one-foot deep. This amount of water would be 1 to 1.5 inches on sand, 1.5 to 2.5 inches on loam, and 2.5 to 3.5 inches on a clay soil. Apply this amount of water to at least the entire area within the drip line of the tree. Do not wet the trunk. Water when the soil becomes dry one to two inches below the soil surface. See the Garden Information Series brochure about saving water in your garden and landscape for information about how to water appropriately.

Fertilizer

Fertilizer needs of citrus trees vary with age. One- to two-year-old, pre-bearing trees need on a yearly basis about 1/8 pound of a complete fertilizer with an N-P-K ratio of about 18-6-12 with minor elements. Three- and four-year-old trees need 1/3 pound and 2/3 pound respectively of the same fertilizer per tree per year. Mature, fully bearing trees need about 5 pounds of the same fertilizer per tree per year. Apply fertilizer in the spring by spreading it evenly under the tree's canopy and water in well.

Mulching

Do not cultivate around citrus trees because their roots are relatively shallow and are easily disturbed. Instead, maintain a three-inch layer of mulch under your trees, using wood chips, leaves, or grass clippings from your yard. Mulches help to suppress weeds, save water, improve soil structure, inhibit root diseases, increase nitrogen, and moderate soil temperature.

Pruning

Citrus need little pruning compared to deciduous fruit trees and ornamental trees. Generally prune lightly, and then only to remove dead, diseased, broken, crossed, or tangled branches. Thin out unproductive stems in the upper part of the tree, any watersprouts (strong, vigorous, succulent, vertical growth), and any shoots arising from below the bud or graft union. Prune just before new growth begins in the spring.

When left alone citrus naturally develop into an even spherical shape with foliage nearly to the ground. Low growth is desirable because it shades the ground and reduces weeds, is usually highly productive, and a ladder is unnecessary to harvest fruit.

Thinning out rather than heading back cuts are preferred when pruning. See the Garden Information Series brochure about pruning for additional information about the types of pruning cuts and how to make them.

Freeze Protection

A light frost is usually not a problem. However, a severe frost or freeze can damage the tree and fruits or even kill the tree outright. If a severe freeze is imminent, wrap trunks well above the bud or graft union with an insulative material like cardboard, newspaper, or specially made thermal wraps. Suspend a canvas cover over the tree. Do not use plastic or allow the cover to drape on or touch the tree. Water well one or two days before the frost.

Consider several strategies to avoid cold and freeze problems. Plant cold-tolerant varieties well adapted to your area. Plant on a slope or in a site with good air drainage or where cold air will not collect. Avoid fertilizing and pruning late in the growing season. Keep trees well irrigated. Plant in containers so trees can be easily moved and sheltered during cold periods.

If frost damage occurs, prune out dead or damaged stems only after new growth starts again in the spring.

Pests and Diseases

Citrus have few major pests and diseases. Aphids, scales, whiteflies, and mealybugs suck plant juices and secrete a sugary substance, called honeydew. Ants usually transport, tend, and protect these pests because they harvest the sugary secretion. Also, a fungus called sooty mold lives on the sugary secretions and blackens the leaf. Small, nearly microscopic mites can cause stippled, yellow leaves and fruits or distorted or misshapen fruits.

Wash pests from leaves with a strong jet of water. Encourage or enhance natural enemies. Use less toxic chemicals first, such as insecticidal soaps or horticultural oils. Control ants and snails and slugs with baits.

Avoid root and trunk rots by watering appropriately and keeping water off the trunk. Do not mound up soil or mulch against the trunk.

Consider integrated pest management and biological control in your garden. See the Garden Information Series brochures about pesticides, plant diseases, vertebrate pests, integrated pest management, and biological control for additional information.

Other Problems

Wind can cause random leaf and fruit scarring or abrasions. Growth spurts late in the season often result in cracked navel oranges. Bark once hidden by leaves but now exposed after pruning sunburns easily so protect it with whitewash or cold-water paint. Fruit drop from May to July, known as June drop, is a normal, self-regulating thinning process. Sudden, drastic temperature changes, too much or too little water or nitrogen, heavy pruning, Santa Ana winds, and some pests can cause excessive fruit drop. Off-season fruits, triggered by disease or too much or too little water, are usually inferior.

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A New Breed of Landscape Contractor

BY TOM ASH, Horticulturist, Director of Conservation Alliances, HydroPoint Data Systems

Three years ago Lalo Mora started his own landscape maintenance company. He had spent years perfecting his horticulture and business skills helping others build their companies into very profitable enterprises. It was time for Lalo to put his vision of environmentally sound landscaping into practice. It was also time, Lalo believed, to pay and treat employees well. It was time for him to open Enviroscaping in Santa Barbara, California.

Today, Lalo employs 70, teaches in the public agency Green Gardener program, and is training his son to eventually take over the business. He estimates the company revenues, after just 3 years is $1 million and growing.

But what makes Lalo and Enviroscaping different? He believes and embraces sustainable landscape techniques and smart irrigation controller technology. Not only does Lalo believe these are the right things to do for the local environment, but he believes he makes more money for his company. You see, Lalo is also a very practical man. He would not jeopardize his company, the jobs of his trusted employees and the future of his families business with an environmental ethic and new technologies if they did not work to improve his ability to make and save money.

The biggest opportunity Lalo sees for his company is selling and installing the WeathterTRAK Smart ET controller. Why? Enviroscaping became the first "certified" contractor company to in a Santa Barbara public agency program to install 200 WeatherTRAK controllers into high water use homes. "It took me 15 minutes to recognize what the WeatherTRAK controller could do for me and my business and for the health of the plants on my sites", says Lalo in a class at Santa Barbara City College. Lalo, and his irrigation specialists, quickly became experts in the installation, activation and set-up of the new smart controller technology. Enviroscaping became a local distributor for the WeatherTRAK controller company HydroPoint Data Systems.

But what makes this different for Lalo's company? The WeatherTRAK reduces the water use on Lalo's sites. He saves them money. "We saved over $600 in one home. The customer used that money and more to upgrade the irrigation system. Then he asked me to relandscape his 2nd home in the mountains. And it all started with installing a smart controller."

Lalo, as the certified WeatherTRAK installer in his area, attended a recent meeting of the Santa Barbara Garden Club. The talk was on water and how to reduce polluted water runoff that comes from home landscapes. After the talk Lalo immediately sold 10 controllers and installations. But, more importantly for his business, "that one meeting generated $80,000 of new work for me", claims Lalo.

The "new work" that Lalo describes is found in upgrading irrigation systems, changing out high water use plants to low water use plants and referrals by the satisfied customers. He helps his customers save money on water bills and improves the appearance of their landscapes. His customers tell their friends and neighbors, and Lalo's company grows.

Lalo's son is now the principle installer of WeatherTRAK controllers for Enviroscaping . Lalo needs to hire another irrigation installer. "I don't want him to touch another controller. I only want him to work with the WeatherTRAK. All the other controllers are dumb. I don't want him to let the other controllers confuse him."

Lalo knew it was time to run his own business. Lalo knew he wanted to do business differently. Now Lalo is providing high quality services, helping to improve the local environment and is growing his business because of his strong belief in efficient water management.

In Santa Barbara, contact Lalo Mora @ Enviroscaping , 805.683.6196, Venado Dr. Santa Barbara, Ca. 93111. WeatherTRAK Smart ET Controllers: www.hydropoint.com or 800.362.8774

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Plant Diseases

BY CHERYL WILEN, PH.D., Integrated Pest Management Advisor, UCCE

An Overview

When your plants or lawn start to decline, either suddenly or over a period of time, it usually indicates that something is hampering their growth. For example, yellowing leaves are often an indication of nitrogen deficiency while high salts in the soil may cause leaf edges to turn brown. These are environmental or nutritional disorders. Improper watering (too much or too little water) may also hamper growth or cause foliage to yellow. Other causes of plant injury that fit in these categories are air pollution, wind, cold, heat, too much light or shade, and improperly used pesticides. Insects may also cause these problems.

However, sometimes disease-causing micro-organisms are responsible for these problems. Some forms of fungi, bacteria, viruses, and nematodes (tiny worm-like creatures usually found in the soil) cause plant diseases. These are called "pathogens". Depending on the type, pathogens can spread by wind, in water, in soil, by contacting another plant, by insects, on seeds or cuttings, or on contaminated equipment.

Three factors must be present for a disease to occur: 1) the pathogen; 2) a susceptible plant; 3) the proper environment for the pathogen to infect the plant. Disease will develop when all three factors are present (see Fig. 1). Disease will not occur when any of the three factors is absent.

Disease symptoms can include wilting, rotting, and dead spots. When looking at a sick plant closely, you may actually see the pathogen. Examples are rust (raised reddish or brown spots on leaves or stems), spores (often black and powdery), or mycelium (fine whitish threads).

The following are some common diseases you may encounter:

• Powdery mildew. A fungus causes this disease. While powdery mildew will rarely kill landscape plants, it can kill some vegetable crops. Signs and symptoms: Leaves and sometimes stems and flowers of plants are covered with what looks like a gray or white powder. Sometimes tiny black dots can be seen if you look at the infected parts through a magnifying glass. Roses, sycamore trees, and some vegetable plants are particularly susceptible to powdery mildew. Control: Wind spreads powdery mildew; therefore, do not prune out infected stems or leaves when windy. Watering the plant at night reduces powdery mildew growth. Sulfur or systemic fungicides can be applied when you first notice the disease.
• Rust. Fungi cause this disease. Wind and splashing water from rain or sprinklers spread rust. Rusts usually do not kill established landscape plants. Signs and symptoms: Numerous dry, small bumps occur on the undersides of leaves. The bumps or pustules are usually red, bright orange, or yellow-brown. The tops of the leaves usually have brown spots. Rusts are common on roses, hawthorn, pine, and fescue grass. Control: Rusts grow best in moist conditions, so avoid overhead watering that keeps leaves wet for a longer period of time. Some fungicides applied in the spring can be helpful. Pruning out infected parts will also reduce spread. Lawns and groundcovers can sometimes outgrow rust damage if they are fertilized as soon as the disease is noticed.
• Wilts. A number of pathogens can cause wilts. Wilt diseases often kill the plant, and there are often no effective treatments after the disease has set in. Signs and symptoms: Usually, bacteria or fungi plug the water-conducting tissue in the plant, or fungi or nematodes destroy the roots. Initially, you may think that the plant is not being watered enough because the leaves or stems droop. If the plant does not recover after a good soaking, you probably have a wilt disease. Many pathogens that cause wilt disease are in the soil. Control: Avoid overly wet soil or potting mix; use resistant varieties (for example use tomato seeds or plants with 'VFN' designation); use only clean potting mix; and avoid wounding the roots and bases of stems.
• Cankers. Certain fungi, bacteria, or even environmental stresses such as under-watering or sunscald, can cause cankers. Cankers are most damaging to trees. Signs and symptoms: A canker is a dead sunken area on a stem surrounded by live tissue. Control: Keeping plants healthy and planting spieces that are adapted to local conditions will help reduce the incidence of cankers. Depending on the cause of the canker, pruning out infected limbs at least six inches below the canker may also be beneficial.
• Damping off. Several different fungi cause damping off, which affects seeds, germinating seeds, and seedlings. Damping off is often mistaken for insect damage. Signs and symptoms: Seeds rot and fail to germinate. Germinated seeds rot and turn black. Seedlings rapidly die and collapse. Often, seedlings will rot at or just above the soil line. Control: Avoid overly wet soil. Plant seedlings or seeds when soil temperatures are optimal for rapid growth or germination. Use only clean potting mixes and pots. Clean used pots in a solution of nine parts water to one part household bleach. Avoid splashing soil when watering. Do not place potted plants on the ground. Sometimes a fungicidal soil drench will help control the disease.
• Sooty mold. This disease is not particularly harmful to plants but does make the plant look unappealing. In rare instances, sooty mold can be so extensive and thick that it blocks sunlight from reaching the leaves. Then, leaves may drop and the plant slowly declines. Signs and symptoms: Leaves are covered with a dark gray or black fungus, giving them a "sooty" appearance. Sooty mold is an indication that there is a heavy infestation of aphids or other sucking insects. The fungus grows on honeydew that falls onto leaves while these insects are feeding. Control: Wash leaves with a strong stream of water. Control insects with insecticidal soap.
• Root Rot. Several different fungi cause root rot, a disease that affects groundcovers, bedding plants, vines, shrubs, and trees. Fungi attack roots, reducing the plant's ability to take up water and nutrients. Signs and symptoms: The plant looks like it does not have enough water. Leaves and new shoots or twigs may wilt. Leaves turn yellow, dry up, and drop from the plant. Shoots, twigs, and branches may die back. Eventually, the entire plant may die. Control: Avoid over-watering. Provide a well aerated soil with excellent drainage. Avoid practices that damage roots or reduce their activity. Plant disease-resistant varieties wherever possible. Sometimes a fungicidal soil drench will help control the disease.

Remember that the best strategy is to prevent diseases. It is easier to prevent than to correct or treat diseases. To prevent diseases, eliminate one or more of the three factors to break the disease triangle described earlier. Select plants that are environmentally well adapted for the intended planting site. Consider soil, light, temperature, wind, water, fertilizer, and insect and disease susceptibility. Use disease-resistant varieties wherever possible. Follow the recommended cultural practices for the selected plants to keep them growing in a healthy manner. It is also important that the problem is correctly diagnosed so that you can apply the best corrective treatment. For example, insects or a disease may cause brown patches in the lawn. Knowing whether it is an insect or disease is essential before considering treatment.

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LandsExpo Update

BY STEVEN JAY PORUS, Publisher

Thousands of Green Industry Professionals will meet at LandsExpo on March 23, 2005. Attendees have the choice of participating on-site at the Texas Station in Las Vegas, or online at LandsExpo.com. Attendees will include professionals in landscape architecture and design, selection, implementation and maintinence of public and private landscapes, parks, golf courses, irrigation, pest control, and more.

Exhibitors will have a unique opportunity to be featured on the LANDSExpo online exhibits and product guide, reaching a National audience. Exhibitors can also schedule "CHATS" at LANDSExpo.com - Promoting products and services while sharing expertise with other Green Industry Professionals. Buyers will be able to view exhibitor's products and services as well as contacting exhibitor for more information or to schedule an through exhibitor's online booth for 60 days prior & 60 days post LANDSExpo.

LANDSExpo's On-site and Online Conference Progarm has applied for continuing education units: ASLA (Individual States TBD), CCA (Nationally), DPR (Individual States TBD), GCSAA (Nationally), IA (Nationally), and ISA (Nationally).

ASLA Credits: Session 1 - Tree Selection, Session 4 - Irrigation Design, Session 6 - Turfgrass Selection, and Session 12 - Irrigation with Reclaimed Water.

CCA Credits: Session 1 - Tree Selection, Session 2 - Pesticides on Turfgrass, Session 3 - Assessing Plant Stress, Session 4 - Irrigation Design, Session 5 - Tree Health, Session 6 - Turfgrass Selection, Session 7 - Soil Issues, Session 8 - Irrigation Efficiency, Session 9 - Pros and Cons Micro Injections, Session 10 - Evaluating Amending Soils, Session 11 - Soil Erosion Control, and Session 12 - Irrigation with Reclaimed Water.

DPR credits: Session 1 - Tree Selection, Session 2 - Pesticides on Turfgrass, Session 3 - Assessing Plant Stress, Session 5 - Tree Health, Session 6 - Turfgrass Selection, Session 7 - Soil Issues, Session 9 - Pros and Cons Micro Injections, and Session 10 - Evaluating Amending Soils.

GCSAA Credits: Session 1 - Tree Selection, Session 2 - Pesticides on Turfgrass, Session 3 - Assessing Plant Stress, Session 4 - Irrigation Design, Session 5 - Tree Health, Session 6 - Turfgrass Selection, Session 7 - Soil Issues, Session 8 - Irrigation Efficiency, Session 9 - Pros and Cons Micro Injections, Session 10 - Evaluating Amending Soils, Session 11 - Soil Erosion Control, and Session 12 - Irrigation with Reclaimed Water.

IA Credits: Session 4 - Irrigation Design, Session 8 - Irrigation Efficiency, and 12 - Irrigation with Reclaimed Water.

ISA Credits: Session 1 - Tree Selection, Session 3 - Assessing Plant Stress, Session 5 - Tree Health, Session 7 - Soil Issues, Session 9 - Pros and Cons Micro Injections, and Session 12 - Irrigation with Reclaimed Water

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