Category: Orchid Doctor

HEAT COLLECTORS: For Greenhouses

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago Heat near the roof is up to 15 dF warmer, and can be returned to the floor area continually by means of installed collectors run by electricity to save from 10% to 20%, of fuel costs; they also low... Read More

HEAT CYLINDER: Greenhouse Automatic Ventilation Control

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago A cylinder and piston actuated by expandible liquid activated by rising and falling temperatures; used to open vents; lifts up to 50 pounds. A69-96+ Read More

HEAT LOSS: The Thermal Radiation Transmittance of Greenhouse Coverings

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago Polyethylene is 70.8% (by far the worst), Mylar film (polyester) 16.2%, PVC 12.0%, glass 4.4%, rigid fiberglass 1.0%; condensation on polyethylene film reduces the heat loss by 50%. OD75-122 Read More

HEAT, SUMMER: Excessive in the Greenhouse

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago In Texas; no glazing material is better than glass; but good shade is required; latex shading is highly efficient for reflecting heat. A74-217 Read More

HEATERS: Back-up for Main Unit

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago If it is ever used in emergency there should be a guarantee obtained from the dealer that it will not produce ethylene when it is used; get a written guarantee. A80-1140 Read More

HEATERS: Catalytic Type

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago Such as made by Coleman; it is not proven but presumably they should not generate ethylene. A77-922; they are approved for emergency heating, although the amount of heat produced is low. A75-35; A7... Read More

HEATERS: Emergency

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago Electric heater causes parching of plants; deflect the hot air stream away from plants, increase the humidity; or, try a polyethylene tube prepunched with holes. A77-619Manually operated propane bu... Read More

HEATERS: Emergency System

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago If the emergency heater fails to operate the last hope is to use water as a continual spray over the plants to avoid freezing and to achieve at least survival of the plants; use a follow-up of fung... Read More

HEATERS: Emergency, for Greenhouses

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago Aladdin series of kerosene heaters are recommended; should burn properly adjusted. A72-631 Read More

ACID OR ALKALINE: Changing the Values

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago Various means can be used: tufa, a limestone form, can be added to paphiopedilums from limestone cliffs; bark composts acidify with age; peatmoss, pine needles, oak leaves in the mix produce acidit... Read More