Maximum Yield USA 2016 June | Page 124

HYDROPONIC BASIL AND CILANTRO “Cilant ro seed is large, rounded and easy to handle. It is best sown into individual cubes, cells or pots of sterilized, free-draining substrate, as seedlings are not suited to transplanting.” Both basil and cilantro are easily propagated from seed. For basil destined for pesto production, specific varieties include Lettuce Leaf Basil, Napoletano and Italian Large Leaf cultivars, which produce sweeter foliage than Genovese types with leaves up to 4 in. long. More exotic basil varieties are used in a range of cultures and cuisines and many are well-suited to hydroponic production. These include the popular Sweet Thai Basil with its distinctive anise-clove flavor, Holy Basil (Kapoor Tulsi) with a spicy flavor and aroma, Cinnamon Basil, Citrus NFT systems are ideal for growing basil. 122 Maximum Yield USA  |  June 2016 or Lemon Basil and Lime Basil with a strong citrus/basil flavor combination, Spicy Basil and Globe/Greek Basil, small-leaved, compact, rounded plants suited to restricted spaces. Cultivars of basil with inbred disease resistance or tolerance to common diseases such as Fusarium and downy mildew are worth considering for larger-scale hydroponic basil production. Basil is most commonly propagated from seeds, which are available in raw and pelleted form. However, cuttings can also be taken and will form roots within seven to 10 days. Seed germinates readily under warm conditions with 75˚F being ideal for most basil types and takes between five to seven days. Rockwool propagation blocks are often used in commercial production, while perlite/ vermiculite, coconut fiber, peat, foam substrates and sand are also suitable provided the medium is sterilized. Basil seedlings are extremely prone to Pythium and other damping off pathogens, so care needs to be taken with watering in the early stages post germination to ensure the surface of the growing media is not overly wet. Once the seedling leaves have expanded, a dilute nutrient solution at an EC of 0.5 mScm-1 can be applied with a pH between 5.8-6.2. Once transplanted into a hydroponic system the EC can be gradually increased and full, high-intensity light levels supplied. Tall, dense stems of many basil varieties benefit from a good degree of air movement and ventilation, up and under the plants to help prevent some of the fungal infections such as Botrytis (gray mold), which these plants can develop under high humidity. Just as with cilantro, basil can be prone to bolting at a fairly young age if the plants are stressed. This may include root restriction, moisture stress, overly dry environments, excessive light or temperatures and overcrowding. Flower buds can be removed from the growing points of plants as they develop, however, once these are seen it is usually mo