Matthiola incana is a cool-weather crop; for us in zone 6a, it gets too hot about mid-June and stock starts to bloom too short, even the varieties that are supposed to be more tolerant of warmer temperatures.  All of ours are grown under cover in high tunnels with plantings both minimally heated and unheated. Florists buy all that we can produce, it works great in bouquets, and with our schedule we can have it blooming for 10 weeks in the spring, starting week 15 and going through week 25. 

Every winter we test our greenhouse soil to come up with a nutrient mix that we apply to the soil in between every planting. Because we turn beds over so quickly under cover, rather than tilling in as we do out in the field, every bed gets ripped out when we are done with it. We then apply a layer of compost and our nutrient mix, tilling it in before any new planting in that bed.

We use Hortonova netting as a planting grid and put two plants per hole, so in our greenhouses there are 5 rows with 2 plants every 6” in row (or one plant every 3”).  We used to plant two starts, in opposite corners of the net, but instead have just started double seeding them in our 128 flats for quicker, easier planting.  The transplants are easier to pull that way also, as long as we plant them soon enough they don’t get root-bound. 

Stock seed produces plants that are singles and doubles, with some hybrid varieties having a higher percentage of doubleness. Some varieties can also be selected to keep only the doubles, meaning that you could pluck out the seedlings after they have developed cotyledons (the embryonic first leaves). When selecting, the plants you want to keep (the double-flowered ones) have lighter color cotyledons. We choose not to select them because we can use the single flowers in bouquets, or just sell them bunched to the florists who are looking for something different. The singles from most varieties are usable, except from the Lucinda series, which quickly shed petals and don’t open up very nicely.

When harvesting, you want the flower stalk to be as long as possible without the bottom set of flowers starting to look bad. We determine if a flower is ready based on how dense the flower buds are when you look down at the top of the stem. You want it to be at least 2/3 bloomed, and the top set of buds starting to stretch out of the center.

Since most of our sales are to florists, we decided to plant by color rather than mixes.  This means I have to choose colors, so I like to run trials before I officially decide. Here are my results; the varieties marked with an asterisk are our favorites, and definitely in next year’s plan.

Cheerful series
This series we have always liked in the past, but this year the stems seemed to be smaller in the middle of the bed, maybe in response to the density. I also read in Specialty Cut Flowers that too much nitrogen can make soft, thin stems, so we will try this variety again next year, but also trial new varieties of these colors to compare.   It only comes in white and yellow.

White: A nice, standard white. Has a little space between the buds, so the stalk is longer.  Will trial against Japan All Double White Surf.

*Yellow: A beautiful buttercream color. Works well with brides who want ivory as opposed to pure white. Will trial it this year against Katz Yellow.

Japan high double series

These are mostly doubles, about 70%, and the singles are usable for the mixed bouquet business, but may not be for sale to florists.

*Blue 2: Our favorite because of waxy leaves and a strong stem.  A great bluepurple, similar to blue lisianthus. A florist favorite.