Popeye had it right – “I’m strong to the finich (sic), cause I eats me spinach”. We’ve been growing a good bit of spinach this winter both inside the high tunnel and outside in low tunnels. There is less weed pressure in the high tunnels, and the leaves are more succulent, but spinach is hardy enough to grow outside through most winters under low tunnels – hoops covered with frost cloth. In the mid-South semi-savoyed versus smooth leaf spinach grows best. “Tyee” has been the variety of choice for several seasons, but our major seed supplier, Johnny’s, substituted “Reflect” this fall, and we like it even better. Some folks wait for the plant until it can be harvested in one bunch – one and done; others like to harvest it as baby spinach; and we like it as a cut and come again crop harvesting it when the leaves are bite size and come back in 10 to 14 days and harvest again.
Chefs love the red edged variety, “Red Kitten”, which we are growing in the high tunnel and will seed again for spring in a few days. It is counterintuitive to think that now is a good time to sow spinach, but the seeds germinate best in soils that range in temperature from 40 degrees to 70 degrees F. Fifty degrees is optimal to produce normal seedlings. We keep the prepared bed warm and dry with clear plastic for a few days before seeding. At fifty degrees F it will take about 12 days to germinate. After watering in the sown seeds, we will recover and begin checking for seedling emergence in about a week – checking each day and then replacing the clear plastic with permeable frost cloth. We’ll pull back the frost cloth on warmer days, and then pin it back before freezing nights.
Spinach is prone to bolting with warmer weather; so, this early start is important for a cut and come again harvest plan. Spinach is in great demand and is one of the more profitable crops. By the time our high tunnel spinach is through harvesting, we should have spinach ready to harvest in the spring beds. Spinach is in the Chenopod family along with its cousins, chard and beets, and for home or market gardeners makes a strong addition to a crop rotation scheme – following a root vegetable in a different family like carrots, potatoes, or radish. It should not immediately follow the cover crop rye.
Recent studies have shown that spinach can offer significant protection against the occurrence of aggressive prostate cancer – the only leafy vegetable with that potency among several that were tested including kale and collards. It is a superfood ranking in the top 10 of green vegetables in the Aggregate Nutrient Density Index developed by Dr. Joel Fuhrman. Darker green leaves will be higher in Vitamin C than paler leaves. Spinach provides antioxidants, helps maintain a healthy cardiovascular system, helps lower blood pressure, aids in cognitive function, and helps protect the lining of the digestive tract. It is low in fat and very low in cholesterol and filled with healthy vitamins and minerals.
Spinach is a super-duper food – grow it, eat it, grow healthier.
Larry Newlin