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Troubleshooting
If mulching and hand weeding prove inadequate, apply the systemic herbicide glyphosate to the leaves of perennial weeds, carefully avoiding the asparagus foliage. In the dormant season, when no asparagus foliage is showing above ground, a contact herbicide such as Weedol 2 will control non-persistent weeds.
The main pests to affect asparagus are slugs and snails, and the larvae and adults of the asparagus beetle.
Thin, spindly shoots may be due to inadequate moisture, especially with young crowns. In established beds the cause is more likely to be overcropping or competition from weeds. Late frosts will cause distorted growth: protect with a double layer of fleece.
