This leafy edible green originated in central and southern Asia but has luckily spread to gardens worldwide. A cool season annual, spinach usually grows best when temperatures stay below 75°F. Mature plants can survive lows down to 20°F: perfect for overwintering. Harvest the richly flavored oval- to triangular-shaped leaves for a treat in salads or as a cooked green and get pumped like Popeye! When plants begin to bolt, they will send up flowering stalks with small greenish-yellow flowers, and leaves will develop a bitter flavor. So make sure to harvest your sweet leaves before this happens!
One of the biggest spinach varieties out there, Giant Nobel—also called Giant Noble or Long Standing Gaudry—is a thick-leafed, lightly savoyed spinach with sweet-tasting triangular leaves and narrow stems. The sweetness will be particularly noticeable when grown in cold weather. Vigorous and large, plants resist bolting and leaves can reach up to 20″ in length, making them productive whether started in spring or late summer. The hardy leaves make it a good choice for canning or freezing. Giant Nobel is also resistant to the common mosaic virus and has been popular since the 1920s.
Seed Depth: 1/2″
Space Between Plants: 8–12″
Space Between Rows: 12–18″
Germination Soil Temperature: 50–75°F
Days for Germination: 7–14
Sow Indoors: 3 to 4 weeks before average last frost.
Sow Outdoors: Beginning in the early spring, when temperatures are consistently 45 to 50°F.
Prefers a mild climate and cool weather. Spinach is quite hardy and can withstand temperatures as cold as 20°F but prefers temperatures between 40–75°F. If you live in a cooler climate zone and are planting very early in the spring or overwintering your crops, cover with straw to keep plants protected in case of extreme cold snaps. If planted too late, your plants may come to maturity when it’s too warm, and they’ll likely bolt quickly and become bitter.
Natural: Full sun. Partial shade in warmer weather.
Artificial: Fluorescent bulbs are a good choice for spinach plants as they don’t care for too much heat.
Soil: Will grow in most soil types but prefers a slightly sandy substrate. A pH of 6.0 to 7.5 will keep plants healthy and nourished.
Soilless: Seeds will germinate in most soilless mixes and prefers those that are higher in nitrogen.
Hydroponics: Will thrive in hydroponic systems in media such as coco coir or perlite.
Aeroponics: Will thrive in an aeroponic system.
Water: Requires low to moderate amounts of water but likes soil that is evenly moist. The highest amounts of water will be required when plants are still in their younger stages. This can be lessened as the plant matures.
Nutrients: Requires moderate levels of nutrients. A balanced fertilizer of nitrogen, phosphorous, and potassium is preferred. Choose mixes that have higher amounts of nitrogen and potassium and lower levels of phosphorus for preparing the beds prior to planting.
Foliar: Apply compost tea or fish emulsion when plants have first been transplanted, about a month following, and just prior to harvest.
Disease(s): Has resistance the the common mosaic virus. Still, watch out for:
Deficiency(s): If leaves are turning yellow, your soil pH may be too high. Adding limestone to your soil can reduce the pH. This may also occur if there is a nitrogen deficiency.
Rotation: Do not follow legumes with spinach. Most crops like being planted after spinach since it’s not very susceptible to soil diseases.
Companions: Grows well with members of the cabbage family, strawberries, fava beans, celery, lettuce, onion, eggplant, and peas. Avoid potatoes.
Harvest: Leaves may be harvested throughout the growing season, but avoid harvesting before the plant has produced approximately 4 to 6 leaves. When ready to pick, start with the outside leaves, allowing the middle leaves to develop. The plant may be harvested all at once as well by cutting at the base of the plant just above soil level.
Storage: As with most leafy greens, leaves will not keep for much longer than a week in the refrigerator, so if planning on consuming them fresh, pick just before you are ready to use them.
History: This heirloom spinach was developed in the Netherlands in 1826 by inbreeding a rare Gaudry spinach that developed both male and female flowers on the same plant. It won the All American Selections award in 1933.
Preserve: May be blanched and frozen for later use.
Prepare: Is commonly consumed raw in salads but is also delicious (and healthy!) sautéed, boiled, or steamed.
Nutritional: Is rich in vitamin(s) A, B, and C as well as many minerals including iron, magnesium, manganese, and folate. Also contains trace amounts of calcium.
Medicinal: Some studies have shown that, due to its high content of folate, spinach can assist in reducing high blood pressure and contribute to improvements in overall heart health.
Warnings: Like chard, spinach contains oxalates which can crystallize and form painful urinary tract stones, so individuals suffering from this condition should consult their doctor before consuming large amounts. Take note that the level of oxalates in spinach can be reduced by cooking.
Bake up some Vegan Spinach and Tofu Ricotta Rolls for an inspired afternoon snack from the garden.