The concentration of Nutrient solution under need to be under 1000 to 1700 ppm. keep ppm low under low temperature and light (indoor ).
Calcium deficiency is one the important ignored factor. Lack of available calcium may cause blossom drop during heat set and browning of early fruits from bottom.
Shoot and root temperatures difference ( not more then 5 degree Celsius)
Relative atmospheric humidity (optimum 50%)
No pollination No fruit development
Tomato is the most commonly grown hydroponic crop in the world. Growing tomatoes in hydroponics is more cost effective compared to conventional farming. It has been observed increasing demand for hydroponics tomatoes mainly due to the health benefits that occur when it is included in the daily diet. Currently Less than 10% of the total production is in cherry, plum, and bell-shaped types. Today in 1.5 million square feet of greenhouses, they are now growing tomato by both the NFT and drip irrigation Rockwool slab systems.
Early or immature flower drop called as blossom drop is on of the common problem faced by hydroponic cultivator. Blossom drop may lead to economic loss if not taken care properly. For hydroponic cultivators solution may be different to conventional cultivators. Lets have a look in to cause and remedies.
Too much Nitrogen in Nutrient Solution
it is the most common cause of blossom drop. Excess or low presence of Nitrogen cause blossom drop. If light is not sufficient then small amount of nitrogen may lead to this issue. We have observed from our many customers that they maintain regular doses of Calcium Nitrate or A:B solution unknowingly. We recommend The concentration of Nutrient solution under need to be under 1000 to 1700 ppm. Keep to ppm lower side under low temperature and light (indoor).
In continuation to first point Calcium deficiency is one the important ignored factor. Lake of available calcium may cause blossom drop during heat set and browning of early fruits from bottom. So keep using Calcium nitrate wisely. If the problem persist then change calcium source.
Tomato flower are perfect flower they contain both male and female part in same flower.. About 99% hydroponics tomatoes were growing under green houses, so there is very less chance for self pollination or biotic pollination (by insect). So pollination tomato flower with brush or hand within 2 days of flowering between 10 am to 4 pm. Remember no pollination means flower drop.
Shoot and root temperatures
In Hydroponics one has to deal with this issue. Usually Nutrient solution colder then environment (Indian perspective), This difference may lead not only blossom drop but lots of other problems. Try to maintain this difference not more than 5 degree Celsius. It is easy to maintain without having exclusive energy consuming devices. Keep shallow nutrient tank and place it nearby to planting system. Keep eye on temperature difference.. Try to maintain root temperature between 20 to 30 degree Celsius. And shoot temperature between 20 to 29 degree centigrade.
to high or low humidity may lead to blossom drop. Maintain humidity range between 40 to 60%. However our recommendation for optimum relative humidity is 50%. Gentle spray of water or application of fogger that product micro droplet is effective. specially in hydroponics tomato cultivation fogger controls temperature gradients and relative humidity. But in extremes condition one must avoid fogger uses.
Please write down your experience or problem in comments or firstname.lastname@example.org with Hydroponics cultivation will try our best to get solution for it
Note :- images used in this post are from VR INTERNATIONAL Bhopal's demo site and plants grown with Total Hydroponics Premix under Shed net house. for more details please visit our website.