That Taproot Goes Down Nearly a Metre. Vinegar Reaches the Leaves.
Docks survive through thick taproots that can extend 90cm or more into the soil. Cut them, dig them, spray them with vinegar – if even a few centimetres of that root remains underground, fresh leaves emerge within weeks. Vinegar burns what’s above ground while the real problem sits safely below.
Does Vinegar Kill Docks?
No. Vinegar can damage dock leaves on contact, but it won’t kill the plant. Docks survive through thick, fleshy taproots that store enough energy to regenerate the plant many times over. Vinegar – a contact-only treatment – burns foliage while the taproot remains completely unaffected underground. Fresh leaves emerge within weeks, often more vigorously than before.
Anyone who’s tried to dig out a dock knows how deep those roots go. DIY surface treatments like vinegar don’t even begin to address the problem.
Why Docks Defeat Vinegar
Understanding dock biology explains why vinegar treatment is futile:
Massive taproots. Dock taproots can extend 90cm or deeper into the soil. These thick, fleshy roots store enormous energy reserves – enough to regenerate the above-ground plant repeatedly. Vinegar applied to leaves has zero effect on this underground storage system.
Regeneration from fragments. Even when you dig docks, any root fragment left behind can regenerate. A piece of taproot just 5cm long contains enough energy to produce a new plant. Vinegar does nothing to address root fragments in the soil.
Vinegar is contact-only. Acetic acid damages plant tissue it directly touches, but it doesn’t travel through the plant’s vascular system. It burns leaves while the taproot – where the plant’s survival depends – remains completely unharmed.
Rapid regrowth. Docks are perennials with substantial energy reserves. Losing leaves is a minor setback they’re well-adapted to survive – grazing animals have been eating dock leaves for millennia without eliminating the plants.
What Actually Happens
Here’s the typical experience with vinegar on docks:
Day 1-3: Sprayed leaves show browning and wilting. The visible damage looks promising.
Week 1-2: Affected foliage dies back. The dock rosette looks reduced or gone.
Week 3-4: Fresh leaves emerge from the crown. The taproot, completely unaffected by your vinegar treatment, sends up new growth with energy to spare.
Month 2: The dock is as vigorous as ever – possibly more so, as the plant responds to perceived threat by pushing harder from its root reserves.
Comparing DIY Methods for Docks
All household remedies fail against dock taproots:
Vinegar: Burns leaves, taproot completely unaffected. Wastes time while the dock recovers.
Salt: Can’t reach deep taproots, poisons surrounding soil. Damages your garden without killing the dock.
Bleach: Surface damage only, environmental concerns. No advantage over safer methods.
Boiling water: Cools before reaching 90cm taproots. Safest failure but still completely ineffective.
What Actually Works on Docks
To eliminate docks properly, you need systemic herbicide that travels from leaves down to the entire taproot:
Systemic herbicide approach. Apply glyphosate-based weedkiller when docks have plenty of healthy leaf area. The herbicide absorbs through leaves and travels throughout the plant’s vascular system, reaching the taproot 90cm below – something no surface treatment can achieve.
Timing matters. Treat when docks are actively growing with substantial foliage. More leaves mean more herbicide absorption and better transport to the roots. Avoid treating when plants are stressed by drought.
Persistence required. Established docks with large taproots may need a second treatment if regrowth appears. Each application depletes more root reserves until they’re exhausted.
A professional-strength treatment delivers the concentration needed to kill even mature docks with extensive root systems.
Go Deep or Go Home
Systemic treatment travels from leaves to taproots 90cm deep. The only way to kill docks properly.
