Fruit and Veg Production Quiz #7

what are organic mulches?

• natural waste products placed around the crops plants and decompose after the season ended

what are synthetic mulch materials?

• first used in the 50s and 60s

• affordable, easy to install, effectively controlled weeds

• reduced time to harvest

• non-degradable plastics and degradable plastics

what are the benefits of mulches?

• conserves water by reducing evaporation

• controls weeds by reducing light irradiation to weed seeds

• reduces labor by reducing

  • weeding

  • irrigation frequency

  • fertilizer applications

• reduce nutrient loss

• reduce insect infestations

• improves and protects soil structure

• reduce incidence of disease helps keep farm cleaner

what are types of organic mulches?

• straw

• grass

• sawdust

• paper

• living mulches

straw mulches

• should be free of weed seeds

• time consuming to apply

• good environment for slugs and rodents

grass mulches

• low C:N ratio

• good source of N for crops

sawdust mulches

• high C:N ratio

• requires addition of inorganic N

• must be composted before use

paper

• available in sheets same with as raised beds

• may be applied with mulch layer

• will decompose facilitating clean up

  • may decompose before growing season complete

living mulches

• cover crop remains alive in aisle during growing season

• helps prevent growth of broadleaf weed species during growing season

• grass often best because growth can be controlled without harming crop

  • post herbicide can be applied at sublethal levels to retard growth of grass mulch

• may require additional nitrogen fertilization to support mulch and crop

• this has been experimented with:

  • asparagus

  • watermelon and other vine crops

  • strawberries

what are examples of synthetic mulches?

• black plastic

• clear plastic

• white plastic

Black plastic synthetic mulches

• traps heat and promotes warming of soil

• goods for melons, watermelons, cucumbers, summer squash, peppers, tomatoes, strawberries, blueberries

• inhibits weed growth by excluding light to seed bed

clear synthetic mulches

• warms soil the best

• allows weed growth because light penetrates seed bed

white plastic mulches

• reflects light best

• soil slightly cooler than black or clear

• repels some insects because leaf undersides are brighter

Black/White combination

reflective colored plastic

degradable plastic

benefits of synthetic mulches

problems with synthetic mulches

what are the two objectives for protected culture?

• Extend the growing season

  • early season planting and extending harvest

• Controlled environmental horticulture

what are cold frames?

purpose: harden seedlings, production of low-growing cole crops

characteristics: temporary structure, unheated, designed for maximum light harvest, designed to use passive cooling

what are hot beds?

purpose: harden seedlings, production of low-growing cole crops - “cold frame” with heat source

characteristics: temporary structure, heated (buried heat cables, manure or compost), designed for maximum harvest of light, designed to use passive cooling

hot caps

purpose: individual covers placed over seedlings, protect plants from suboptimal temps, can be removed temporarily when conditions improve

characteristics: temporary structure, unheated, designs (formed plastic, film plastic, paper, milk cartons - may overheat on sunny days)

floating row covers

purpose: cover placed over plant rows, protect plants from suboptimal temperatures, can be removed temporarily when conditions improve

characteristics: lightweight fabrics, vary thickness, allow water to infiltrate

low tunnels

high tunnels

purpose: hoop structures placed over plant rows (may be placed over multiple rows), protect plants from suboptimal temperatures, remain in place until conditions improve (may be constructed to remove the cover, cover may be placed over structure towards ends of the season to extend harvest)

characteristics: film plastic, metal or plastic (PVC) ribs to support, varying thickness, ventilation (some have roll-up sides)

what are quonset greenhouses?

• most economical greenhouse design

• may be short or tall sided

• facilitated film coverings

• most commonly used design

what are Even-Span greenhouses?

• roof pitches are equal

• side wall height ranges from 8 to 25 typically covered with ridged plastic

what are greenhouse cultural systems?

• cultural systems, organics, hydroponics, aquaponics

protected structures for organic production

• function: uses soil and compost and substrates, grow plants in ground or containers, may be heated or no

what is hydroponics?

• culture of plants in a nutrient rich liquid medium with or without an inert support substrate

• liquid medium contains all nutrients essential for plant growth at the desired concentrations

• supports may be sand, rockwool, and perlite

why do we use hydroponics?

• crops can be grown where no suitable soil exists or where the soil is contaminated

• improves plant yield

  • more flowers and fruit

  • increased flower and fruit size

  • improved quality

    • plant receive balanced nutrition

• reduced insect and disease problems

  • plants are better able to resist pests and diseases because of increased vigor

  • diseases can be eradicated easily in closed systems

• can conserve water and nutrients

  • irrigation can be automated

  • nutrients are applied individually as needed

• the plant environment can be easily monitored and controlled

• reduced labor

what are the main points on why we use hydroponics?

• crops can be grown when no suitable soil exists or where the soil is contaminated

• improved plant yield

• reduced insect and disease problems

• can conserve water and nutrients

• the plant environment can be easily monitored and controlled

• reduced labor

• easy to start a business

hydroponic bag culture

• plants are grown directly in bags that contain an inter substrate

  • perlite

  • horticultural rockwool

  • vermiculite

  • sand

• system may be set up to capture leachate and reuse it or leachate may be contained within the bag