Troubleshooting
Marram Grass problems — and how to fix them
Marram Grass (Ammophila arenaria) is generally low-drama, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Decline in stable, fertile soil
Marram grass suffers a well-documented 'senility decline' in fixed, stable dunes or garden borders where sand burial ceases; it thins out and loses vigour without the stimulus of fresh sand deposition.
Coleophora leaf miner and caterpillars
Larvae of Coleophora species and various moth caterpillars feed on the leaves; damage is rarely severe enough to warrant treatment in naturalistic coastal plantings.
Prevent marram grass problems before they start
Most marram grass issues are care-mismatch, not bad luck. Dial in the basics:
Marram Grass problems — FAQ
Why is my marram grass decline in stable, fertile soil?
Marram grass suffers a well-documented 'senility decline' in fixed, stable dunes or garden borders where sand burial ceases; it thins out and loses vigour without the stimulus of fresh sand deposition.
Why is my marram grass coleophora leaf miner and caterpillars?
Larvae of Coleophora species and various moth caterpillars feed on the leaves; damage is rarely severe enough to warrant treatment in naturalistic coastal plantings.