Post category: Skills of Greenhouse growing

 

Watering 

 

Plants in a greenhouse need extra care because of the high temperatures generated and the exclusion of natural rainfall.

 

Christmas cherry with other greenhouse plants

 

Cooling

 

Ventilation on hot days is necessary to keep plants cool. About 25° Celsius is an ideal maximum for most plants. Beyond that, growth slows down and stops. High temperature levels can be reached from late spring onwards.

In summer, ventilation alone might not be enough, so shading can be necessary. Apply Coolglass, or Summer Cloud, in June or early July and remove it at the end of August. A simple way of cooling the house on really hot days is to damp down the floor. Ventilation in winter and spring, on dry, bree days, dries the greenhouse atmosphere, helping disease control.

 

Feeding

 

Greenhouse plants must be fed much more often than plants outdoors. The frequent watering that greenhouse plants receive tends to wash the soluble plant nutrients from the restricted reserve of a pot.

Feed little and often – even as often as once a week for large, quick-growing plants early in the growing season. Liquid feeding is simplest to use and most effective. Take care not to feed a dry pot, for fear of scorching the roots.

 

Hygiene

 

Pest and disease damage is usually more severe in a greenhouse, where the warm conditions are ideal for insects and fungi, and predators are absent. Remove old and diseased plants, or pest-ridden plants, to break the cycle of infection. Control pests and diseases when they appear.

Wash down the glass, pots, trays and benches in the winter with household disinfectant. There are no products approved for domestic use in disinfection of greenhouse soil. If the soil is ‘tired’, replace it with fresh soil. If there are root disease problems, grow non-susceptible crops. Flood the greenhouse soil in early spring by watering heavily to leach out excessive salts left over from frequent feeding the previous year.