|MadSci Network: Botany|
Margaret, Excellent question! You might be surprised to find out that, as far as basic hydroponics go, not much has changed. There has been no radical change in the methods we use to grow the plants. We are still working with the same types of water cultures and replacement medias (like rockwool and perlite) that have been common place for the last couple of decades. That said, we have seen some real advancements in a couple of areas that have made hydroponics more efficient and cost effective. First off, greenhouses have become more energy efficient. While this might not sound like a big deal, heating and cooling is the biggest expense a grower has. Next, plastic has pretty much replaced materials such as wood, concrete, and metal in hydroponics systems. Plastic is cheap, lightweight, strong, does not contaminate the nutrient solutions with metals, and is easier to clean or, if need be, replaced. Plastic pretty much revitalized interest in hydroponics in the late 1980ís by bringing the cost of building a system way down. By using computerized growing systems, a grower knows they have a constant watchdog checking their greenhouse and crop. These systems can automatically open vents, turn on fans, pull shade cloths, and even place a phone call if the power or water were to fail. Only a few years ago, these systems were expensive and only used by large commercial ventures or research facilities. Now they are much more affordable and accessible to smaller growers. As we get gain more experience growing crops in certain systems at certain climates, we refine our growing techniques and make subtle changes to improve yields. Not all that long ago, growers would use one nutrient solution for everything. Now we know that we can get better crop yields by giving the plants more or less of certain nutrients at different stages of growth (vegetative, flowering, and fruit set). And this knowledge base continues to expand improving our ability to grow hydroponically. Finally, there is a renewed interest in locally grown, high quality produce, especially here in the United States. Sure we can grow lots of tomatoes in California, but to get them here to the Midwest, they have to be harvested green and hard as a baseball. This drastically reduces the taste compared to a vine-ripened tomato. Obviously, we canít grow tomatoes here in Indiana in the winter unless we grow indoors, for which a hydroponic system is well suited. Some people are willing to pay higher prices for what they perceive as higher quality food. While this is not a technological advancement, this change is economics is still a very important driving force in increasing the usage of hydroponics. I hope I answered your question! Eric Biddinger Extension Educator Purdue Extension Ė Porter County
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