A Note from Sara

February in Florida is a funny month. It's our version of deep winter — which means it dipped into the low 50s last Tuesday and I actually wore a jacket to the greenhouse. I know our friends up north would laugh at that, but cold is relative, and so is what you crave when the temperature drops. For me, that's soup. Big pots of it, simmering on the stove while I catch up on research papers in the evening.

That combination — science and comfort food — is basically my entire personality, so I decided to lean into it for this month's newsletter. We're going to talk about the nitrogen cycle in aquaponics (stick with me, it's fascinating once you see how elegant the system is), share some genuinely good winter soup recipes that use microgreens as more than a garnish, and clear up the sprouts-versus-microgreens confusion once and for all.

What We're Reading

The Nitrogen Cycle in Aquaponics, Explained

I get asked about aquaponics at almost every market appearance. People are curious but intimidated, and I think that's partly because explanations tend to either oversimplify ("the fish feed the plants!") or drown you in biochemistry. The truth is somewhere in the middle. The nitrogen cycle is the engine that makes aquaponics work, and understanding it — really understanding it — changes how you think about growing food entirely. Fish produce ammonia. Bacteria convert it to nitrites, then nitrates. Plants absorb the nitrates. Clean water returns to the fish. It's a closed loop that nature figured out long before we did.

Read the full nitrogen cycle explainer →

Winter Soups with Microgreens

I want to be clear about something: microgreens on soup are not just decoration. A handful of spicy radish microgreens stirred into a bowl of roasted butternut squash soup right before serving adds a peppery bite that cuts through the sweetness in a way dried spices can't replicate. The heat wilts them just enough to release their oils without destroying the nutrition. This post has five of my favorite combinations, tested in my own kitchen over the past two winters.

Read the soup recipes →

Sprouts vs. Microgreens: What's Actually Different

I had a customer at the Sarasota market last week who genuinely believed microgreens and sprouts were the same thing. She's not alone — this is probably the single most common misconception I encounter. The differences matter, especially when it comes to food safety. Sprouts are germinated seeds eaten whole, root and all, grown in water. Microgreens are young plants grown in soil or a growing medium, harvested above the soil line, with true leaves or cotyledons. Different growing methods, different risk profiles, different flavors.

Read the full comparison →

Seasonal Tip: Humidity Control in Winter

Even in Florida, winter brings lower humidity — and that changes your growing environment more than you might think. Lower humidity means your growing medium dries out faster, which is actually good for preventing mold, but it also means you need to water more consistently. I check moisture levels twice a day in February instead of once. If you're growing at home, the simplest test is pressing your finger into the growing medium about half an inch deep. If it feels dry, water gently from the bottom. Overhead watering in lower humidity can create uneven moisture pockets that lead to patchy germination.

Florida Spotlight: Aquaponics in the Sunshine State

Florida is quietly becoming one of the most important states for aquaponics research and commercial production. The University of the Virgin Islands model — which pioneered much of modern aquaponics — has been adapted extensively by Florida researchers, and UF/IFAS has several ongoing projects exploring tropical species integration. Closer to home, I've been visiting small aquaponic operations around the state, and the diversity of approaches is impressive. Some are growing tilapia and lettuce. Others are experimenting with shrimp and herbs. The common thread is a commitment to closed-loop, low-waste food production that makes sense in our climate.

Quick FAQ

Q: Can I grow microgreens in an aquaponic system?

A: You can, but it's not the most practical approach for most people. Microgreens grow so quickly — 7 to 14 days — that they don't take full advantage of the aquaponic nutrient cycle the way longer-season crops do. The setup and maintenance overhead of an aquaponic system is better justified by crops like lettuce, herbs, or fruiting plants that stay in the system for weeks or months. That said, I've seen growers use aquaponic water as a nutrient solution for watering microgreen trays, which gives you some of the benefits without the complexity.

Until Next Month

Spring is right around the corner, and with it comes the kind of energy that makes you want to plant everything at once. Resist that urge for two more weeks. February rewards patience. In the meantime, make some soup.

Keep growing,
Sara Johnson
President, Wholly Water Farms