Maximum Yield USA 2015 January | Page 26

ASK The Experts I have a flood and drain hydroponic system. I have tried growing many types of plants, but the best performers in the system were lettuce, cucumbers and tomatoes. As I only have a small greenhouse and wish to share the produce with my family, I want to grow the most productive plants. Can you suggest the best seeds for me to purchase for lettuce, cucumbers and tomatoes? I live in northern Florida. Thank you! – H. James Schroeer The best varieties for a small, hydroponic greenhouse in your climate are hybrid types of tomato and cucumber plants, and heat-tolerant lettuce cultivars. Hybrid seeds will give you significantly higher yields and multiple disease-resistant properties. They perform well under hydroponic growing conditions where they receive ideal levels of nutrients. Lettuce is essentially a cool-season crop and can struggle in warm growing conditions, so selecting more heat-tolerant or bolt-resistant types is recommended to help prevent problems such as upward stretching, or the development of tip burn under high temperatures. The following would be my seed recommendations for a hydroponic system in Florida: Tomatoes Beefsteak: Trust F1 and Geronimo F1. These are both grown commercially in greenhouses and are ideal for hydroponics. The fruit is large, so fruit trusses may need some support due to their weight. These varieties also have multiple disease-resistant properties. Hybrid tomato plants need plenty of potassium when the fruit is developing, so I recommend using a highquality fruiting or bloom nutrient formulation at this stage. Cherry: Flavorita F1 or Sakura F1. Both are red cherry tomatoes with a good, sweet flavor and multiple disease-resistant properties. They are less prone to splitting or cracking than other cherry types. Cucumbers There is quite a wide range of cucumber types that can be grown hydroponically. Here are some of my top recommendations: Long, seedless Dutch type: Tyria F1. Fruit are 14-in. long, great-tasting, thin-skinned and non-bitter. They also have some resistance to powdery mildew, which is a huge advantage when it comes to cucumbers. American slicer type: Corinto F1. Fruit are 7-8-in. long, have good disease resistance and are highly productive in hydroponics. Mini cocktail type: Iznik F1. Harvested when just 2-3-in. long, and also called snack cucumbers, these cucumber seeds are a good variety for hydroponics as they produce a lot of thin-skinned fruits. 24 Maximum Yield USA | January 2015 Lettuce It pays to try growing a wide range of lettuce types, depending on your personal preferences, of course. However, the following types are proven performers in hydroponic systems: Green butter lettuce: Rex. Pelleted Rex seeds are the best in terms of handling and germination. This lettuce is ideal for Florida’s climate. It is slow to bolt and very reliable. It also tolerates downy mildew. Green frilled type: Muir. It is a medium-sized, light green, open and slow-growing variety. Muir is fairly heat tolerant and has a good flavor. Salanova: For a mix of different lettuces and a surefire way to impress friends and family, the latest hydroponic lettuce trend is the Salanova lettuce types that produce compact heads of leaves that are all totally uniform in size and shape. I recommend the Salanova Home Garden Mix pelleted seed mix, which will produce a range of colored Salanova types. This seed is a little more expensive than other lettuce types since it is a reasonably new development, but it is well worth the investment, particularly with the deep red types. All of these seed varieties are available online from Johnny seeds (johnnyseeds.com) in different-sized packs. Good luck with your hydroponic greenhouse this season! Kind regards, Dr. Lynette Morgan Suntec International Hydroponic Consultants Dr. Lynette Morgan Dr. Lynette Morgan holds a B. Hort. Tech. degree and a PhD in hydroponic greenhouse production from Massey University, New Zealand. Lynette is a partner with Suntec International Hydroponic Consultants and has authored several hydroponic technical books. Visit suntec.co.nz for more information.