The spear will become woody to support the small branchlets of fern-like foliage. The foliage produces carbohydrates for the plant and sends it down to the crown for next year's spear production. Asparagus is very drought tolerant once established and can usually grow without supplemental watering because it seeks moisture deep in the soil. However, newly-planted crowns will benefit from irrigation during dry spells. Otherwise the plants will become stressed and vigorous growth will be impeded.
Insects Inspect the foliage throughout the season for insect feeding.
Asparagus beetles chew on the foliage, causing the stem to turn brown and reducing the yield the next year. Spray the ferns with an approved insecticide when beetles are seen. If beetles are numerous, it might be wise to remove plant debris at the end of the growing season to reduce overwintering sites for the beetle. Managing Insects in the Home Vegetable Garden for more information. Disease Rust is the most common and troublesome asparagus disease.