Produce Grower: What are some of the basic steps growers should take to establish a sanitary growing environment?
Eric Smith: For starters, a lot of people think sanitation is maybe sweeping or pressure washing. I tell all of the growers that that’s cleaning, and it looks clean, but you haven’t killed anything. We always recommend a true sanitation step, like SaniDate 5.0 or even a pre-cleaning with GreenClean Alkaline Cleaner. The alkaline cleaner helps break down some of the soil particles and some of the debris that’s in the concrete or in the ground cloth. The SaniDate 5.0 is an actual kill step where you’re going to kill active and dormant spores and cells of all of the pathogens. Sometimes growers just use a leaf blower, or sometimes they just sweep everything out or they spray it out and then pressure wash it. That looks clean. But in doing that, they’ve actually just blown everything around the facility and spread spores everywhere.
PG: When you only do surface-level cleaning, what effect does that have on algae, bacteria and other issues?
ES: Sweeping, pressure washing and other cleaning methods are only cosmetic. They don’t sanitize anything. You’ll have a quicker, faster recurrence of algae, of bacteria, of water molds if you don’t sanitize properly. Downy mildew is another common issue. They can survive cosmetic cleaning steps, but then they thrive again when conditions are favorable again when there’s more water introduced, the greenhouse warms up or there are more nutrients introduced via fertigation.
PG: How often should a grower properly sanitize their greenhouses? And how long does it take to sanitize?
ES: I would recommend sanitizing once annually. But if possible, especially with some of the annual growers and fall season growers, do it between crop cycles. Sanitize after your mums and before your poinsettias or after your poinsettias and before your spring annuals. Sometimes mums and poinsettias overlap, so it’s not possible to sanitize then. You should at least do it before those plants are in the greenhouse and start with a clean greenhouse environment. It can be done in one day. It’s a lot less labor-intensive than people think, especially with our chemistries. GreenClean Alkaline Cleaner can be sprayed on all surfaces to remove greases and oils and dirt deposits. You can sweep and get everything visibly clean, but there’s still organic matter that’s trapping pathogens, bacteria and algae within that organic matter. GreenClean Alkaline Cleaner is a strong detergent to clean the surfaces — the benches, the walls, the floors — and trays and pots too. Using SaniDate 5.0 to kill the spores, to kill the bacteria, to kill the algae and fungi is key. Because SaniDate 5.0 is a no-rinse, no scrub formula, you can use them in the same day. Use the alkaline cleaner in the morning and once that’s dry, you can follow that up immediately with the SaniDate via spraying or foaming. You let it dry on its own and you’re essentially done. — Interviewed by Chris Manning