Xtremehorticulture

Harvesting Herbs and Easily Damaged Vegetables

Basil Growing in the hot Las Vegas Valley of the Mojave Desert Nothing is worse than harvesting herbs and eggplant and by the time you get them in the door they are withered or soft and no longer firm. Or your products didn’t last very long in their cooler. Here are some suggestions on how to harvest these tender plants from the garden and keep them fresh. The ideal time to harvest most herbs is as early in the morning as possible. This is the time of day when temperatures are lowest, humidity is highest and winds are low. This is also the time for herbs when those volatile oils that are so important are at their peak and flavors are best. Harvesting should be at a time when the flower buds are just starting to form but before they open. When the flowering cycle begins, the plant begins to shove nutrients at the flowers and subsequent seeds which takes precedence over the production of leaves and stems. Flower formation indicates this loss of nutrients in leaves and stems is about to happen. After some familiarity you will begin to visually predict when this occurs as you note changes in the growth of the plant. If at all possible, spray herbs and soft vegetables with a mist of water 10 to 20 minutes before harvesting to wash dirt from the surface, cool the plant down and rehydrate the surface. Check with your local ordinances to make sure this is permissable prior to sale if you are selling. In the case of vegetables, the larger the vegetables the longer it takes to cool the plant down. So don’t expect that a quick rinse of eggplant for instance to have much impact in cooling the fruit down internally. In our dry climate the cooling effect from spraying a plant down with water may last ten minutes at best and then the temperature begins to climb back toward the air temperature quickly. On the contrary, a light mist of water on the surface of most delicate herbs and leafy vegetables will cool the plants down considerably. Make sure you take a clean bucket with cool, clean water (nonchlorinated would be best) into the field with you. During summer months the water temperature should be at least cool to the touch and cooler than the air temperature. For those requiring more exacting guidelines you should have temperatures about 55 to 65 F. There are some plants that can be packed in ice while others cannot. Icing is usually reserved for cold hardier plants like broccoli, spinach, cilantro, parsley, green onions, and Brussels sprouts. Icing more tender plants will result in injury. The four major enemies to plant quality and storage life occur after harvest: damage from handling, low humidity and water loss, high temperatures, and direct sunlight. Do everything you can to keep these enemies from damaging your harvest. Damage from handling. Harvesting requires a sharp and sterile knife or shears. Herbs and soft vegetables should be severed from the plant cleanly without tearing or ripping and lifted rather than pulled and immediately immersed in clean, cool water. Any surface tearing or scarring impacts the quality of herbs and soft vegetables and their storage life. If you have long fingernails or wear jewelry on your hands that could tear or rip, wear thin plastic gloves to protect these tender plant parts from damage. This may sound like these precautions are “overboard” but if you expect to store these plant parts for any length of time, damage to the surface of the plant allows water to be lost and disease pathogens entrance. All herbs and soft vegetables have to be inspected for damage and sorted for quality. Sorting or grading of products, if not done carefully and out of harsh conditions, can intensify damage and result in even more losses. Low humidity and water loss. Our desert climate is naturally low in humidity. That is great for growing plants but not so after harvesting. As soon as the herbs or vegetables are severed from the plant its source of water is removed, air enters the stems, water no longer moves through the severed plant part. Plants with roots attached can lose water from leaf and stem surfaces and water from the roots replenishes lost water. This keeps the leaves and stems hydrated and cool. Evaporation of water from leaves and stems helps cool the plant. As water is lost from severed plant parts their freshness and quality is compromised. Immersing them in cool, clean water immediately after harvest helps keep these products hydrated and fresh. Keep these plant parts out of the wind, direct sunlight and high temperatures which drive excessive water loss. High temperatures. It should go without much explanation that harvested plant parts should be kept cool unless you are dealing with vegetables that require high temperature and humidity after harvest such as sweet potatoes. Direct sunlight. The energy from the sun can be deceivingly destructive. I don’t know how many times I have told people in the field to put harvested products in the shade, even if it is under the shade of other plants. This is one of the most commonly abused practices after harvest. I observed small-scale producers in Kenya on the slopes of Mt. Kenya harvesting products and putting them in direct sunlight to be picked up by the co-op truck a few hours later. To top it all, these products were sorted and graded at the co-op headquarters by co-op members in DIRECT SUNLIGHT! Coop members then did not understand why half or more of their harvest was rejected by the exporter. Cleaning. A light salt solution (two tbs per five gallons or 35 g. per 20 L) can clean products of insects without damaging plant parts. Straight table salt, sodium chloride, has two chemicals that can cause plant damage; sodium and chloride ions. If too intense, damage will result. A better salt might be a potassium

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Preventing Thrips Damage to Nectarine Fruit

Western flower thrips are the major problem with growing nectarines in the Las Vegas valley. Nectarine fruit damaged by Western flower thrips. These tiny insects appear at the time of bloom and begin ripping and tearing into the surface of the immature fruits as soon as the blossoms drop from the tree. If left unchecked they continue to rip and shred the fruit surface with their rasping mouthparts causing the fruit to scar and leak sap. The leaking sap crystallizes and remains attached to the fruit where it is scarred. The resulting fruit is deformed, ugly and looks inedible. But it is not. The fruit is still good and tasty. To keep the fruit from becoming scarred and deformed, pesticide applications must be used. One of the best organic approaches is to use the insecticide called spinosad. Spinosad is applied to the fruit with spray applications until harvest. It should be combined with a spreader/sticker additive to the spray mix. Follow label directions. It is a must to change off your pesticide applications with others to prevent the possibility of developing chemical resistance to this product. This is called rotating your chemical applications. Other organic sprays you can alternate with include insecticidal soap, and neem oil.

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Desert Fruit Trees Evaluated

Fruit Tree Evaluations for the Desert Fruit can be easy to grow in the desert. We dont have that may disease problems due to our low humidity and if you are isolated from commercial or backyard producers, insect problems can be minimal. I just finished our fruit evaluations at the Orchard in North Las Vegas and would like to share them with you. Fruit trees were originally planted at the Orchard site beginning in 1997. Fruit trees are grown in 10 X 10 spacings in orchard rows. All trees were planted as bareroot plants and amended with compost at the time of planting. Wood mulch from green waste, provided by Tony Valente of First Choice Tree Service, covers the surface of the orchard to a depth of 4 to 6 inches. Fruit trees are pruned annually to heights of 6 ½ to 7 feet to keep the Orchard “ladderless”. Although not a certified organic orchard, pesticides used are “organic” in nature following a “least toxic” philosophy. Orchard volunteers, consisting of both Master Gardeners and community volunteers, provide most of the work at the Orchard. Fruit from the Orchard is sold to local restaurants, farmers markets and the local community to recover the costs of production. After recordkeeping of a variety is completed, trees are removed and replaced with other varieties to gather information on the varieties of fruit that grows best and produces the best fruit in the Mojave Desert. Evaluations categories are: Top Choice for those fruit trees providing exceptional fruit and tree health; Honorable Mention for those which provided very good fruit and very good health in our climate and Under Review for those which have not been growing long enough for multiple year evaluations or have been inconsistent. Evaluation trials were conducted from 2005 – 2009. Fruit tree evaluations were made through taste evaluations of the fruit and midsummer evaluations of the trees themselves and their performance at the UNCE Orchard in North Las Vegas, Nevada. Most of the fruit trees were provided by Dave Wilson Nursery in cooperation with research and demonstrations provided by the University of Nevada Cooperative Extension. More general information about these fruit can be obtained by visiting Dave Wilson Nursery’s website at: http://www.davewilson.com/homegrown/homeindex1.html. Wine grapes were provided by Duarte Nursery and nopal cactus provided by faculty at the Universidad de Sonora in Hermosillo, Mexico. Almonds Most almonds do extremely well in southern Nevada and make excellent landscape trees. They have few pest problems but the desert ground squirrels can clean out a tree in a day. Recommended rootstock: Nemaguard but others have performed adequately over the long term. Top Choice · All in One – Genetic Dwarf, Self pollinating · Garden Prince – Genetic Dwarf, Self pollinating, flowers white with purple Notable Mention · Price · Nonpariel Under Review · Carmel · Neplus Ultra In Mediterranean regions they eat young almonds or spring almonds fresh from the tree, the entire nut, when it is about half an inch long or so, husk and all. At this stage the center of the nut is still gellatinous. It is at this stage they can be eaten like a snack. What do they taste like? A little sour but refreshing with a touch of sweetness and very little to remind you of an almond. You can also harvest green almonds when the husk is in the green stage at a more “juvenile” stage. This is around late March or April here when the interior seed is white on the outside but the gelatinous mass on the inside has disappeared. At this stage they taste alot like pine nuts and can be used like pinoles. In the desert the remaining nuts can be left to dry on the tree and do not mold due to our very low humidity but you better get them harvested before the ground squirrels get them.

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