Introduction to Horticulture Plant: Digitalis Term: Hydroponics
- Plant type: Biennial, Herb,
- USDA Hardiness Zones: 4a to 8a
- Exposure: partial shade to full sun
- Bloom Color: Pink, Purple, White
- Bloom Time: Late spring to early summer
- Landscape Uses: Border, Container, Massing, Specimen, Woodland garden
- All or parts of this plant are poisonous
- Suitable for cut flowers during 2 nd year
- Extract used for heart medicine
- The term "hydroponics" refers to growing crops without soil.
- Inert medium, such as gravel, water, sand, peat.
- A nutrient solution is added containing all essential elements needed by the plant.
- Hydroponic production is very space intensive.
- Grow almost any herbaceous plant.
- High value food crops or horticultural plants.
- Commonly grown crops include lettuce, tomatoes, cucumbers and herbs.
- The crop varieties grown hydroponically are bred specifically for greenhouse production.
COMMON HYDROPONIC METHODS
- Water culture: Crop roots are immersed or bathed in a continuous flow of nutrient solution. Often this is done in beds or troughs within a greenhouse. Tops of plants need supports.
COMMON HYDROPONIC METHODS
- Crop plants are grown in a solid media that provides anchorage and support much like soil does.
- Materials often used as growing media include gravel, sand, perlite, soilless mixes , and rockwool.
- The media is enclosed in beds, bags or blocks.
- The nutrient solution is flooded or drip irrigated past the roots.
- Plant top support is necessary for taller crops.
ADVANTAGES OF HYDROPONICS
- Grow out of season or zone.
- Grow at periods of lowest supply. Best prices.
- Higher crop yields from smaller areas. Planting density is limited only by available light.
- An example of comparative yields for tomatoes is:
- Soil grown: 5 to 10 tons per acre;
- Hydroponic: 60 to 300 tons per acre.
- Plants can mature faster and more evenly
- Crops can be vine-ripened and sold immediately.
- Soil-borne insect and disease problems are reduced
- Crops do not need to be rotated.
- Crops do not need to be cultivated or weeded.
- Nutrient application timing and nutrient quantities can be custom tailored to a particular crop's specific needs.
DISADVANTAGES OF HYDROPONICS
- The initial investment is high
- Greenhouse heating can be quite expensive in the winter months.
- More skill is required than for traditional methods.
- The grower/operator must be highly trained in plant nutrition and system operation and maintenance .
- Monitored through EC readings
- EC = electric conductivity
- Gives a general reading of the solute content of a liquid
- Each fertilizer is different
- Use water soluble fertilizer
- Want ~ 50 ppm N for constant flow irrigation
- Tub holds 50 gal, how much fertilizer should be added?
- 1 PPM = .0038g/gal, 28g = 1 oz
- 1 ppm = .0038 ÷ 28 = ? oz/gal
- 50 ppm = 50 X .0001357 = ? Oz/gal
- .006785oz/gal x 50 gal = ? Oz N
- 0 .34 oz of N ÷ 20% = ?oz total fertilizer