Mizuna – the Gateway Mustard.
Mizuna is a very mild flavored crop, with thin juicy white stems and green ferny leaves which add loft in salad mixes. (“Loft” is the word for the “puffiness” of frilled salad crops, helping them occupy space and not collapse in the bottom of the bag or bowl like wet green corn flakes.) This tolerant crop is very easy to grow, tolerates cold wet soil, and variable weather. It is fairly heat tolerant (well, warm tolerant), and cold tolerant to 25°F (-4°C).
We used to just grow just one planting, sowing it outdoors September 24, transplanting it into our hoophouse October 22. It regrows vigorously after cutting and we harvest leaves from November 27 to January 25 or even to March 7, when it becomes a mass of small yellow flowers (edible!). In the winter, once the plant gets bigger and bushier, we switch from harvesting individual leaves to a method we call the “half-buzz-cut.” We gather the leaves on one side of the plant and cut them with scissors about an inch above the soil. Then we chop them into our salad mix harvest bucket. The plants look odd with half their leaves still full-size and half shorn, but this method seems to help the plant regrow quicker. The big leaves can photosynthesize and feed the regrowing leaves.
Next we tried Purple Mizuna, but we were disappointed with the weak color and a constitution less-robust than green mizuna.
Ruby Streaks and other Frilly Mustards
After a few years of growing mizuna, we discovered Ruby Streaks. It has a much stronger color, and I admit, a much stronger flavor. Our diners don’t generally like pungent greens, but this one, cut small and mixed with other salad greens, gained wide approval. We have moved on to include Golden Frills and Scarlet Frills, and for a while Red Rain. We find the Scarlet Frills and Golden Frills bolt (go to seed) later than Ruby Streaks and Mizuna.
Adding a Second Sowing
We added a second sowing, this one direct-sown in the hoophouse, on October 30, and the next year shifted the date to November 9. These direct-sown mustards can be used for baby salads after only 21 days (when thinning the rows, for instance). Thin to 8″–12″ (20–30 cm) apart, to grow to maturity in 40 days. We sow mizuna and the spicier mustards at the same time, usually 6 rows to a 4’ (1.2 m) wide bed, maybe a total row length of 50’ (15 m). This sowing gives us harvests from February 26 to March 24, several weeks later than the September 24 sowing.
When we learned our hoophouse soil had nematodes some years ago, we searched for resistant crops and were happy to learn that Brassica juncea greens were resistant. Although mizuna is not B. juncea, the more pungent frilly mustards are, so we focused on growing those, and ignored mizuna for several years.
Adding a Third Sowing
We were looking for a late winter nematode-resistant crop to follow our Koji, which I think bolts up to a month earlier than my long-time favorite Yukina Savoy. We tried the frilly mustards, sown February 1, and they were very successful. We got harvests from March 24 to April 23, a very worthwhile month of greens! I like greens that are harvestable in March and April, because this is really our Hungry Gap, the time when the stored crops are running out and the outdoor spring-planted ones haven’t really got producing much yet. I’m a bit suspicious of our record-keeping on the April 23 date – I suspect it was really over before that. It seems unlikely that this sowing lasts 30 days when the second one only lasts 26 days.
By trial and error, we found that our last worthwhile hoophouse sowing date for frilly mustards is February 12.
Trying a Fourth Sowing
As part of a renewed effort to manage the nematodes, last year we added in a fourth sowing, on October 30. I haven’t got any records for that harvest to hand. I do remember though, that we had about as much “Frills” (as we now call them) as we could eat. We planted 30’ (9 m) in the first sowing, 50’ (15 m) in the new extra planting, 48” (14 m) in the November 9 sowing, and a whopping 120’ (36 m) in the February 1 sowing.