CUCUMBER CONUNDRUMS
Young cucumber plants in a drip-irrigated hydroponic system .
Fruit deformities can have a number of causes , including insect feeding on the young fruitlets .
Cucumbers come in long , short , and rounded types , with plenty of varieties to choose from .
Young fruitlets may wither and die back when the plant is already carrying a heavy fruit load .
FLAVOR AND FRUIT QUALITY
Some fruit quality issues are caused by maturity stage or genetics . Older , openpollinated varieties are particularly likely to develop bitter flavors when harvested over mature . Modern greenhouse hybrids , on the other hand , have largely had this tendency bred out . Plant stress , unfavorable growing conditions , and pests and diseases can also create flavor issues . In particular , slow-growing plants under less-than-ideal temperatures and humidity levels often develop stronger , unpleasant flavors . Light levels also affect cucumber fruit quality . Light produces assimilate for fruit growth and insufficient light will result in poorly flavored and under-sized fruit . Under severe light deficiency , young fruitlets will often abscise and fall from the plant . Cucumbers particularly require high light levels , similar to those given to tomatoes . Canopy shading can be an issue , however , as cucumbers take up a lot of space ( ideally , plant density is one to 1.5 plants per square meter ). Finally , excessive heat , high EC , and low humidity can also result in plant wilting and fruit that lacks crunch and has a short storage life .
FRUIT LOADING , DROP , AND SHRIVELLING
Commonly reported issues with some cucumber crops are the abscission and drop of small fruitlets , or the shrivelling and dying back of young fruit on the vine . This can simply be a result of heavy crop loading ; the plant will limit the development of new fruitlets if there are already a number of larger fruit dominating the supply of assimilate produced in the leaves . Other common reasons are a lack of sufficient light for fruit growth , nutrient deficiencies , or sub-optimal growing conditions ( particularly , cool night temperatures ). If this is the case , most healthy plants will eventually start to set fruit once growing conditions are suitable .
PESTS AND DISEASES
Cucumbers are prone to root rot diseases under certain growing conditions , especially those that restrict oxygenation around the root zone or oversaturate the growing medium . Temperatures that are either too high or too low can also stress cucumbers and make them more susceptible to pathogen attack .
Cucumber seedlings can develop pythium if overwatered , so a sterile growing medium and clean water source are recommended during the early propagation phase . Larger plants are less susceptible to root rot disease unless the root system is damaged in some way through water or EC stress or , more commonly , when plants are over irrigated and suffer root zone suffocation . When it comes to pests , the most common and problematic for cucumbers are mites . These pests thrive in warm , dry indoor gardens and can be difficult to eradicate . Inexperienced growers also often misdiagnose the early signs of mite infestations on cucumber plants as the pests are too small to see easily and the foliage symptoms are easily missed in the early stages . Mite damage starts as a slight bronzing , speckling , or loss of color on the foliage . Later on , superfine webbing can be seen in the leaf axils and mites , which look like tiny red dots , appear on the undersides of leaves . The use of a magnifying glass is helpful when identifying mites and early and repeated control is essential . Also , increasing humidity and damaging down with water sprays can help reduce mite populations .
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CUCUMBERS particularly require high light levels , similar to those given to tomatoes .
136 Maximum Yield USA | December 2016