Summer Season and Lettuce Cultivation – What are the Crucial Attention Points?

Published on 01/07/2024

Summer comes with challenges for lettuce cultivation that does not take a break during the holiday season. In this article, we want to share some findings and learnings with the aim of supporting growers to continue operations during the summer period, focusing on water health issues.

We commonly see that bad water health during the spring/summer season in hydroponically lettuce cultivation is one of the most crucial challenges that growers face. Most of the time, it is mentioned as Pythium. Even though it is one of the factors influencing water health,  it is not the only cause.After having conducted various trials and visited facilities worldwide, we concluded that starting by having the “basic cultivation principles right” helps prevent the infection on serious damageable production levels. Moreover, other than prevention, the following steps defined by Cultivators’ own experience, help an already damaged crop to slowly overcome the heavy root issues.

Below you can find some of the principles that we believe need to be implemented before moving into the warmer seasons of the year;

• Irrigation water temperature – we advise that during the summer season, a difference of 3-4°C should be applied between the greenhouse and the water temperature
• Dissolved oxygen levels in the irrigation water – if no oxygen dosing is applied, then it is advised to do so. The optimum levels are between 15-20 ppm
• Water recirculation – depending on the system, longer irrigation shoots on NFT to refresh frequently the contaminated water. Better water movement in DWC ponds
• Proper gutter/float disinfection – removing old roots and dirt is as important as disinfecting with high-pressure hot water
• Proper water filtration– it is important that at least 2 filtration methods are used
• Proper freshwater disinfection – be sure that the freshwater is properly disinfected, at the right temperature, and has the right O₂ levels
• Healthy young plant production – proper germination, transplanting on time, having the right microclimate, and applying the right irrigation strategy on young plant production are very important steps that are often forgotten
• Genetics – Choosing more resilient cultivars and constantly testing multiple varieties and lettuce types on the system can help you avoid big production losses at difficult moments

Among others, these and some other basic principles are often overlooked. Nevertheless, we see that they are as crucial as the proper climate management in the growing facility.

Do you have any following questions or concerns? Do you want to know more about the products and concentration that we advise? Please contact us and our experts will assist you further.