How to Grow Purple Asparagus
Choose an area for establishing your purple asparagus bed., Test the soil., Plant a cover crop to keep the weeds down., Raise the organic matter in the soil., Do companion planting., Plant in trenches., Put the crowns in the trench., Fill in the...
Step-by-Step Guide
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Step 1: Choose an area for establishing your purple asparagus bed.
Find an area in your garden where you can cultivate asparagus for many years.
Choose an area with good drainage and preferably with light, sandy soil.
Make sure that it is fully in the sun.
Avoid areas with poor air flow or where asparagus has been planted before., Have your soil tested for pH levels and acidity.
Alternatively, purchase a soil testing kit to do this yourself.
Purple asparagus needs soil with a pH level between
6.5 and
7.0.
Repeat the tests every three years to see if you need to make any changes to your asparagus bed.Amend the soil with lime if the pH level is too low.
Till the lime deeply into the soil. , A year before you plant your purple asparagus, grow buckwheat on the site in the summer.
Grow rye or wheat on the site in the fall and winter.
This will also increase the organic matter in the soil., Begin preparing the asparagus bed in late fall.
Spread a three inch (7.62 cm) layer of mulch, manure, leaf mold, wood shavings, or compost into the bed.
Dig or till it down to about 10-12 inches (25.4-30.48 cm) below the surface.
Turn the soil so it covers all of your organic matter., Plant asparagus with basil, beets, lettuce, parsley, spinach, strawberries, and tomatoes.
Maximize the nutrient levels in your garden by planting purple asparagus with strawberries, which root on different levels.
Don’t rotate asparagus onion, leeks, chives or garlic, which can transmit diseases to your asparagus planting., Dig your trenches about 8-10 inches (20.32-25.4 cm) deep in sandy soil.
If you have more clay in your soil, dig the trenches about 6 inches (15.24 cm) deep.
Lay down some phosphate fertilizer prior to planting.Start planting when temperatures are between 75 and 85 degrees Fahrenheit (23.88 and
29.44 Celsius) during the day and around 60 degrees Fahrenheit (15.55 degrees Celsius) in the evenings. , Plant the crowns between 8 and 12 inches (20.32 and
30.48 cm) apart in the center of the trench.
Prior to planting, put 2 inch (5.08 cm) mounds of soil in the spots where you will place the crowns.
Put the crowns above the roots.
Be sure to remove any rotten roots before you plant the crowns., Don’t fill in the trenches completely unless you have very sandy soil.
Cover the crowns with about 3 inches (7.62 cm) of soil.
After six weeks, cover them with another 3 inches (7.62 cm) of soil.
Fill in the trenches completely after the plants have gone dormant in the late fall or spring., Hand weed and hoe to remove weeds during the planting year.
There aren’t really safe herbicides for purple asparagus in its first year.
Pull out weeds early and often.
Also mulch your asparagus bed to prevent weeds., Check your plants regularly for insects.
The most prevalent pest is the asparagus beetle.
Look for its dark, slug-like larvae on the ferns.
Other signs to look for include insect bites and brown stems.
Hand pick the larvae off of the ferns.
Spray with an approved pesticide to get rid of adult asparagus beetles.Adult asparagus beetles are red with black spots or metallic-colored with yellow spots. , Look for signs of diseases like wilting and yellowing mature ferns in hot summer weather or light green oval lesions on the shoots that eventually appear as dark blisters.
Don’t over harvest the plants and make sure you plant in soil that has good drainage and high pH levels to prevent crown rot.
Prevent asparagus rust by removing infested ferns.You can apply an approved fungicide on a seven to ten day cycle starting when the ferns are about 3 feet (0.9 m) (0.914 m) high.
Stop using the fungicide in mid-September., During the first year, water your purple asparagus during dry spells.
Avoid overwatering because the plants can’t tolerate water-logged soil.
Overwatering can also contribute to crown rot and rust.
Mulch your asparagus beds well during the summer months to retain moisture in the soil.
Use straw, hay, or grass clippings and be sure that your mulch doesn’t contain weeds or weed seeds., Start harvesting your purple asparagus three years after planting the crowns.
Only harvest for one month at first.
This will let the plant establish its strong root system, which harvesting can weaken.
After this, harvest the purple asparagus spears from early spring through May or June for about eight weeks each season., Don’t let the asparagus get much taller or the stalks will be very tough and difficult to harvest.
Snap the stalks at the soil surface to harvest.
Avoid cutting the stalks, which can injure the crown buds that will produce the next spears., This will help retain moisture in the asparagus bed and allow the plants to grow extensive storage root systems.
Allow the asparagus to continue growing after your harvesting season is over.
If necessary, stake your plants and tie them with strings for extra support.
Plant the rows parallel to your garden’s prevailing wind patterns so the plants can support each other. -
Step 2: Test the soil.
-
Step 3: Plant a cover crop to keep the weeds down.
-
Step 4: Raise the organic matter in the soil.
-
Step 5: Do companion planting.
-
Step 6: Plant in trenches.
-
Step 7: Put the crowns in the trench.
-
Step 8: Fill in the trenches.
-
Step 9: Weed carefully.
-
Step 10: Control for insects.
-
Step 11: Fight diseases.
-
Step 12: Water the plants.
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Step 13: Plan your harvest.
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Step 14: Harvest daily when the spears are about 6-8 inches (15.24-20.32 cm) high.
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Step 15: Encourage fern growth.
Detailed Guide
Find an area in your garden where you can cultivate asparagus for many years.
Choose an area with good drainage and preferably with light, sandy soil.
Make sure that it is fully in the sun.
Avoid areas with poor air flow or where asparagus has been planted before., Have your soil tested for pH levels and acidity.
Alternatively, purchase a soil testing kit to do this yourself.
Purple asparagus needs soil with a pH level between
6.5 and
7.0.
Repeat the tests every three years to see if you need to make any changes to your asparagus bed.Amend the soil with lime if the pH level is too low.
Till the lime deeply into the soil. , A year before you plant your purple asparagus, grow buckwheat on the site in the summer.
Grow rye or wheat on the site in the fall and winter.
This will also increase the organic matter in the soil., Begin preparing the asparagus bed in late fall.
Spread a three inch (7.62 cm) layer of mulch, manure, leaf mold, wood shavings, or compost into the bed.
Dig or till it down to about 10-12 inches (25.4-30.48 cm) below the surface.
Turn the soil so it covers all of your organic matter., Plant asparagus with basil, beets, lettuce, parsley, spinach, strawberries, and tomatoes.
Maximize the nutrient levels in your garden by planting purple asparagus with strawberries, which root on different levels.
Don’t rotate asparagus onion, leeks, chives or garlic, which can transmit diseases to your asparagus planting., Dig your trenches about 8-10 inches (20.32-25.4 cm) deep in sandy soil.
If you have more clay in your soil, dig the trenches about 6 inches (15.24 cm) deep.
Lay down some phosphate fertilizer prior to planting.Start planting when temperatures are between 75 and 85 degrees Fahrenheit (23.88 and
29.44 Celsius) during the day and around 60 degrees Fahrenheit (15.55 degrees Celsius) in the evenings. , Plant the crowns between 8 and 12 inches (20.32 and
30.48 cm) apart in the center of the trench.
Prior to planting, put 2 inch (5.08 cm) mounds of soil in the spots where you will place the crowns.
Put the crowns above the roots.
Be sure to remove any rotten roots before you plant the crowns., Don’t fill in the trenches completely unless you have very sandy soil.
Cover the crowns with about 3 inches (7.62 cm) of soil.
After six weeks, cover them with another 3 inches (7.62 cm) of soil.
Fill in the trenches completely after the plants have gone dormant in the late fall or spring., Hand weed and hoe to remove weeds during the planting year.
There aren’t really safe herbicides for purple asparagus in its first year.
Pull out weeds early and often.
Also mulch your asparagus bed to prevent weeds., Check your plants regularly for insects.
The most prevalent pest is the asparagus beetle.
Look for its dark, slug-like larvae on the ferns.
Other signs to look for include insect bites and brown stems.
Hand pick the larvae off of the ferns.
Spray with an approved pesticide to get rid of adult asparagus beetles.Adult asparagus beetles are red with black spots or metallic-colored with yellow spots. , Look for signs of diseases like wilting and yellowing mature ferns in hot summer weather or light green oval lesions on the shoots that eventually appear as dark blisters.
Don’t over harvest the plants and make sure you plant in soil that has good drainage and high pH levels to prevent crown rot.
Prevent asparagus rust by removing infested ferns.You can apply an approved fungicide on a seven to ten day cycle starting when the ferns are about 3 feet (0.9 m) (0.914 m) high.
Stop using the fungicide in mid-September., During the first year, water your purple asparagus during dry spells.
Avoid overwatering because the plants can’t tolerate water-logged soil.
Overwatering can also contribute to crown rot and rust.
Mulch your asparagus beds well during the summer months to retain moisture in the soil.
Use straw, hay, or grass clippings and be sure that your mulch doesn’t contain weeds or weed seeds., Start harvesting your purple asparagus three years after planting the crowns.
Only harvest for one month at first.
This will let the plant establish its strong root system, which harvesting can weaken.
After this, harvest the purple asparagus spears from early spring through May or June for about eight weeks each season., Don’t let the asparagus get much taller or the stalks will be very tough and difficult to harvest.
Snap the stalks at the soil surface to harvest.
Avoid cutting the stalks, which can injure the crown buds that will produce the next spears., This will help retain moisture in the asparagus bed and allow the plants to grow extensive storage root systems.
Allow the asparagus to continue growing after your harvesting season is over.
If necessary, stake your plants and tie them with strings for extra support.
Plant the rows parallel to your garden’s prevailing wind patterns so the plants can support each other.
About the Author
Betty Butler
Specializes in breaking down complex DIY projects topics into simple steps.
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