At Tangly Woods, we sure do love us our spinach! Ever since childhood, when I used to sometimes order the salad bar at a restaurant and crunch my way through a nice pile of raw spinach leaves, I have had a taste for it. When we married, Janelle introduced me to her family’s habit of spinach salad with boiled eggs and that magic dressing; we eat that salad as often as we can when spinach is in season…no wonder our first 10 years of gardening together yielded no appreciable cooked spinach and certainly no more than a pittance to freeze: We ate it all fresh before it ever got that far! The winter of 2014-2015 was the first winter we had enough spinach in the freezer to use substantially, if a little more sparingly than we might ideally prefer, until the fresh, overwintered spinach started coming ready in late March. Spinach dip, potato-crusted spinach quiche, spinach with sweet potatoes, chicken, and chick peas in a bone-broth soup…it was a good winter.
Spinach is not, for all gardeners, the easiest or most predictable crop to grow. It is highly sensitive to available nitrate in the soil, so rich and vibrant garden soils are generally required to get good results. It also seems to give people germination fits sometimes, having trouble pushing its way out of crusted/smothered soils. Lighter, higher organic matter soils are much more amenable to spinach culture (and nearly everything else!). Slugs seem to enjoy the freshly sprouted cotyledons, so that is who I generally blame when I see lots of germination and then a week later the row is full of gaps. There are organic-approved slug baits and they seem to work…if you want to use these put them out on the soil surface right when you seed or transplant the spinach.
Mulch is wonderful in many ways, but I tend to forgo it on our spinach plantings because: a) at the time of year spinach is growing there is usually plenty of soil moisture, b) it harbors slugs which can wipe out seedlings in a hurry, c) for simultaneous seeding and mulching it’s hard to find a mulch the seeds can sprout through but weeds can’t, d) for later mulching the plants grow so low to the ground you can hardly get mulch under the leaves, and e) our most likely mulch for such small plants would be grass clippings; trying to wash spinach which is laced with dried grass is a hassle. So ours usually grows in soil that is otherwise bare, spaced closely enough that the mature plants mostly shade their own roots. Often I will mulch the footpaths between beds, but I am careful to keep it a little away from the plants themselves. I control weeds by shallow cultivation with a stirrup or traditional hoe between rows when plants are young, and once the plants are thinned to six inches apart in the row I can often cultivate between plants, too. For weeds that emerge too close to the plant for hoeing, I am afraid there is no avoiding some hand weeding.
When it comes to planting patterns and harvesting, people generally deal with spinach one of three ways: sow in rows and thin to the appropriate spacing for best plant vigor, start in flats and plant out in an efficiently spaced bed-filling pattern, or (if the weed seed load is low enough) broadcast seed in a bed relatively thickly and cut the crowded leaves—haircut style—periodically en masse for salads. At our house we have settled on the thinned-row approach, though we cluster three rows together, spaced eight to ten inches apart, in beds spaced at three feet on center (one foot for walking, two for planting, and so on). Our weed seed load is still pretty high, and since our productive plants double as our breeders/seed producers, we need the opportunity for selection that thinning the plants and picking them as individuals provides. We also delight in big, ruffled leaves for our salads (none of these flat baby-leaf salads lying daintily and discreetly on a salad plate…we like to make a meal of it!), and we enjoy a little more substance in the cooked spinach, too. Thinning to individual plants with plenty of space gives us those vigorous leaves. Whether in rows or evenly spaced in beds, plants picked as individuals should be allowed to mature their leaves pretty well before picking, and any yellowed leaves are better removed if there is time, as they can be more of a drag on the plant than of any help in producing more growth. Our market garden friends prefer to start their plants in a greenhouse and transplant them—evenly spaced in the bed—and harvest all the mature leaves on each plant in one swipe, allowing the whole plant to get a good head of steam before grabbing its big bunch of leaves in one hand and slashing it off with a harvesting knife held in the other. The spinach fills up the bins pretty fast that way. They then have to sort out the substandard leaves while washing, but they have decided that system is quicker overall. I have no argument with that, but it is not the way we do it on our scale.
In my opinion, spinach is one of the easiest plants to save seed from. When the plants start to bolt (always before the gardener is quite ready), you simply fail to remove the plants and they follow through with their flowering and seed-setting work. Seed-savers should know that spinach plants come as male and female, so half of the plants will produce pollen and no seed, and the other half will produce seed, but no pollen. They pollinate by wind, so the plants need to be within reach of each other to pollinate effectively. I would be concerned about genetic diversity if I had fewer than ten of each sex in any given generation. Ideally, the more prime specimens you can have setting seed in your population, the more diverse and resilient your population will be over time. Overproduction of seed is not a problem…you don’t have to use it all, and it allows you to winnow it more harshly, skewing your type towards heavier, more easily-winnowed seeds which produce more robust seedlings. Also friends and neighbors may be glad for some of the extra you may have, especially when they see the results of your having selected for several generations in favor of a strain that thrives in your locale. When “rogueing” (selecting out the non-conforming plants), I look for plants that produce only small leaves, any that are suffering from disease, any with leaf deformities that make washing especially challenging, slower-growing plants, and I also try to yank the first few outliers that bolt earlier then their neighbors. Once the majority of the plants have begun to bolt, I relent. If you want to take it a step further and you have enough specimens that you are able to save seed from only the best, look for plants that have lots of broken-off leaf stems—these are the ones you have clearly managed to pick lots of spinach leaves from during the season—and consider sampling the plants for flavor and texture. The small leaves that grow out from the side of the flower stalk are perfectly edible and I have never known a spinach leaf to be bitter, but if you are saving seed I do not advise picking them, since the plant needs energy at that time to successfully set vigorous seed. It is already asking a lot of them to demand most of the plant’s leaves during the main season!
When the seed stalks have mostly dried and turned light brown, collect the stalks during dry weather and hang them in bundles in a shed or other dry, airy location away from mice or birds. I often collect in two or more batches as plants become ready. If you wait too long to collect, the stalks and seed coats become black and mildewy, reducing seed viability and making threshing and winnowing more of a mess. After a few weeks of drying, I thresh by stomping, crushing, and scuffing the seed-laden stalks with my booted feet (making sure my boots are perfectly dry and relatively clean) in a kids’ wading pool with a textured bottom set on a concrete floor. After removing the empty stalks and other big pieces (sometimes a screening device can be nice for this but it is not necessary), I winnow by pouring the seed from a smallish stainless steel mixing bowl into a biggish one in front of a box fan (I position myself to the side of the air stream since I don’t want spinach chaff blown into every available orifice and clothing seam on my person). I start at low speed and work my way up, being careful to pour so as to catch the bulk of the good seed while letting the chaff and lighter seed blow over the edge.
So far we have mostly worked with Bloomsdale spinaches, since they were commonly available and the leaves had that thick, robust, ruffled quality we so craved. Also overwintering was important to us for season extension and the Bloomsdale performs well that way. I don’t know that it is the ideal spinach for broadcasting in thick patches, though the fans of this method may feel free to contradict me on that. We have used seed from both Longstanding and Winter strains of Bloomsdale, and have saved seed from fall-sown and spring-sown plants for our supply. I couldn’t notice a huge difference in the performance of strains, but I wasn’t paying exquisite attention…I banked on our selection process delivering the results we needed in due time.
And it seems to have worked! What we have going right now is a strain of Bloomsdale that may or may not perform differently for others from what they can get at the hardware store, but which, for us, is now becoming remarkably consistent and dependable for both overwintering and spring sowing. The winter of 2013-14 saw two minus-ten Fahrenheit weather events, one with snow cover and one with little or no snow. Most of the spinach came through fine. 2014-15 saw minus five, but we had snow cover, and I can’t see any significant losses in the spinach patch (both years with no cover). In the future, I may try to split out the population into winter specialists and slow-bolt spring specialists, but for now they are all in the same pot. Spinach is one of the few plants (of the many we save seed from) that we have enough seed of and I feel confident enough in to begin spreading it around. Local folks may try a sample for free…if you want larger quantities of seed, let’s talk about a price!