Did you know the asparagus is actually a part of the lily family? There are over 300 varieties, but only 20 are edible.
Asparagus is a vegetable for the patient gardener. It is a long-surviving perennial that can last up to 15 years as long as it is in a soil with excellent drainage, but it takes two years or more before the spears can be harvested. Asparagus prefers a soil with a ph of 6.5 – 7.5 and should be fertilized with a 10-20-10 analysis. The fertilizer should be tilled down to six inches at a rate of 20 pounds per 1000 square feet.
The yearling crowns (stem and root) can be planted in the ground as long as the soil is at least 50 degrees. Each crown will yield about 1/2 pound of spears per season. If you wish to plant the seeds of the asparagus, that can be done. But, the constant caring of the infant seedlings can be time consuming. Within a year, the crowns must be dug up and replanted further apart. The spears will not yield until the second or third year.
Harvesting can occur for 3-4 weeks the second year and 6-8 weeks thereafter. Be sure not to cut the spears at the soil level or you may damage the crown.
Nutritional Content of Asparagus
The asparagus spear is very high in Vitamin K and potassium. One cup yield 114% of the Daily Recommended Value an average adult needs in their diet. They are also high in fiber and folate (65% of the DRV), Vitamins C and A, B complex and iron, yet like many vegetables are low in calories.
Because of its high levels of folate, asparagus is excellent for cardiovascular health. Ancient cultures believed it to be an aphrodisiac, though that is unproved. It does help blood flow and fetal nervous system development in utero. Thus many OB GYNs recommend asparagus to their patients.
Asparagus contains a certain enzyme that humans cannot digest called inulin. But that is a good thing, because the beneficial bacteria in our digestive tracts love it. When they thrive, we experience less harmful bacterial infections.
An average one cup serving contains up to 288 mg of potassium and less than 19.8 of sodium. Combined with the enzymes called asparagines so prevalent in each spear, it makes a good natural diuretic.
Tips on Preparing Asparagus
The stems should be deep green with green or purplish tips on them. They should also be well rounded. Look for a little woodiness around the base so it doesn’t dry out too much after harvesting.
Asparagus must be kept in an airtight container in the back of the fridge to protect the folate levels. Eat them within one to two days of harvesting to get the optimum nutritional benefit.
The spears can be served hot or cold. Cut the fibrous base away, wash them thoroughly in cold water, then tie the stems together with a string to steam them. If you can stand them upright, that is the best way to prepare the stalks.
Two words of advice – never let them soak in water or they will get soggy, and if you are to serve them cold, blanch them in iced water immediately after steaming them.
Asparagus Cautions and Concerns
- Patients on anti-coagulants should consult with their physicians before including asparagus in their diets due to the high levels of folate, potassium and vitamin K.
- Never cook asparagus stalks in an iron pot because the tannins in them will react unfavorably to the iron.
- Some people experience a strong odor in their urine after digesting asparagus. However, there is no need to be alarmed. It is simply a matter of the chemical breakdown during digestion.
- Asparagus contains purines. If you believe you have been diagnosed with a purine sensitivity check with your doctor before eating too many asparagus spears.
Want to learn more about growing asparagus, its health benefits and preparation?