3 11 Light & Temperature
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Transcript of 3 11 Light & Temperature
Horticulture
Term: Hardiness Zone
Plant: Begonia
Begonia semperflorens-cultorumWax begonia Plant type: Annual USDA Hardiness Zones: Annual Height: 6" to 24" ,Spread: 8 - 12" Exposure: shade to partial shade Bloom Color: Pink, Red, White Bloom Time:, Late spring to Early fall Leaf Color: Green, Purple, Variegated Uses: Bedding, Container, Landscaping standard due to low maintenance
requirement
Hardiness Zones
a geographically-defined area in which a specific category of plant life is capable of growing, based on it's ability to withstand the minimum temperatures of the zone.
How cold it gets in winter
US Hardiness Zones
Hardiness Zones
Virginia
USDA ZONE 7a
Zones are designated by lowest expected temperatures during winter
Zone #s are in increments of 10 A & B designation are in increments of 5
So if you buy a flower with a hardiness of 8, will it make it through the winter here?
How about if it is 5?
Thermoperiod
Thermoperiod refers to daily temperature change.
Plants produce maximum growth when exposed to a day temperature that is about 10 to 15°F higher than the night temperature.
This allows the plant to photosynthesize (build up) and respire (break down) during an optimum daytime temperature, and to curtail the rate of respiration during a cooler night
Greenhouses program temperature for thermoperiods
Vernalization Requirement of plants to go through a
period of cold before they can flower.
Photoperiod
The relative lengths of alternating periods of darkness and light affecting the growth and maturity of plants esp. flowering and dropping of leaves.
The Light Spectrum
Plants only use radiation energy in the visible spectrum.
Chlorophyll does not absorb in the green spectrum
Why?
Photoperiods
Equinox – Fall & SpringEqual hours of day and nightSpring equinox Mar 21
Solstice – Winter & SummerWinter – Shortest daySummer – Longest day
Plants Short-day plants- don’t flower in summer
ChrysanthemumsPoinsettiasCoffee
Long-day plants- only flower in summerGrains, Carnations
Day neutral plants – photoperiod doesn’t matter
Onions
Variety depends on where you live Northern Areas Southern Areas
Which area gets more light in summer?
Exposure
Shade: No or only early morning sun Part shade: site that gets only 2 to 6 hours
of direct sun each day. Part sun: same as part shade but includes
more afternoon sun. Full sun: at least 6 hours of sun per day
including noon.
Today
Plugs
Soil Texture
Soil Fertility