How to apply tree wound sealer
Updated: October 2026
You already have the pot on the bench, usually Provanto Arbrex, and the cut is waiting. This is how to apply tree wound sealer as a thin film on clean wood, with gloves on, without turning a sticky gel into a cracked lump. It assumes you have decided the cut should be painted. If you are still choosing a bottle, start with the [tree wax comparison](/hub/trees-and-palms/tree-wax). The Products Compared editorial team wrote this on 16 October 2026 from retailer label steps, the Arbrex safety data sheet, Royal Horticultural Society pages, and amazon.co.uk reviews. We did not film a pruning job. A qualifying purchase can earn a commission at no extra cost to you.
You already have the pot on the bench, usually Provanto Arbrex, and the cut is waiting.
You already have the pot on the bench, usually Provanto Arbrex, and the cut is waiting. This is how to apply tree wound sealer as a thin film on clean wood, with gloves on, without turning a sticky gel into a cracked lump. It assumes you have decided the cut should be painted. If you are still choosing a bottle, start with the tree wax comparison. The Products Compared editorial team wrote this on 16 October 2026 from retailer label steps, the Arbrex safety data sheet, Royal Horticultural Society pages, and amazon.co.uk reviews. We did not film a pruning job. A qualifying purchase can earn a commission at no extra cost to you.
Our top picks
| Badge | Product | Brush | Stated fill | Form | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  Kiyonal Kiyonal cut paste, 100 g | – | 100 g tube | Paste | 8.4 | about £11.99 | View offer |
 Provanto Provanto Arbrex, 300 g | Cap | 300 g in the title | – | 9.2 | about £7.80 | View offer | |
| Preis-Tipp |  Vividye Vividye sealer, 500 g | Small brush in reviews; bullets do not name one | 500 g | Paste | 7.6 | about £10.99 | View offer |
On this page
Clean the cut before any film
Paint sits on the surface you give it. Brush loose bark and torn fibres off the wound so the gel meets wood, not a flap that will lift next week. Do the job on a dry day. A film laid over rainwater traps that water against the cut, which is one reason pruning guides dislike thick seals. Leave the branch collar. That swollen ring at the base of the limb is the tree's own boundary. Cutting it flush makes a worse wound than a slightly longer stub that still shows the collar. If you have already cut into the collar, a heavier coat of sealer does not repair it. The gel does not replace bark. A workable example is a plum side shoot about the thickness of a finger, cut just outside the collar with bypass secateurs, the ragged edge pared, then left until the surface is dry. Only then does a thin coat make sense, and only if that plum is in the narrow case where a seal is justified. If you have not decided to paint, read should I paint pruning cuts before you open the tin. If you are still unsure whether a bottle belongs with you, the buying questions sit on the tree wax buying guide.
The Arbrex label sequence
Retailers that sell the 300 g bottle, including J M Garden, B&Q, and Polhill, reprint the same short sequence. Squeeze gently. Lay a thin coat across the cut and over the edges. Put the cap back on. When that coat has dried, you may add a second thin coat. Work in dry weather. The bottle in this set is ASIN B07BWZDDJX, 300 g, made in the United Kingdom. Gentle means a small pressure on the sides. Reviewers who squeeze hard say the brush cap flies off and the gel jumps onto the ladder, a sleeve, or their hair. A thin coat is a film you can still see the wood through, not a pad. The second coat waits until the first is dry. Stacking wet gel is how people build the thickness that later cracks. Some retail pages also tell you to warm a bleeding cut with a blow lamp before sealing. Do not do that from this guide. The Arbrex safety data sheet for model 86600040 identifies ethanol and classes the product as flammable. A flame next to that gel is a fire risk, and the Royal Horticultural Society says not to paint bleeding cuts at all. Sap is a calendar problem, not a job for heat.
What UK reviewers had to change
Across the first 50 UK reviews of that Arbrex listing, the gel covers the wood and then punishes careless handling. People report it on hands, clothes, hair, and ladders. The built-in brush wastes product. If the cap shoots off, stop squeezing, wipe the neck, and press the cap back on square. An old toothbrush is what several reviewers switch to when the cap brush is too coarse. Keep that brush for this job only. One reviewer used methylated spirits on tools. That is a single reviewer's clean-up for metal, not a method for skin and not a way to thin the gel. Wipe bulk off skin and wash with soap and water rather than scrubbing with solvent. The other repeated failure is cracking. Reviewers who laid a thick coat say the dry film split or peeled and left wood exposed. Gloves before you start save more time than any clean-up afterwards.
Other packs in this set
The 500 g Vividye tub is not the same gesture as the Arbrex bottle. UK reviews describe a sealed inner bag, disposable gloves, and a small brush. Cut the bag open over the tub, stir, then brush a thin layer. The seller says a second coat after 2 hours on deep wounds. The film dries extremely bright green, so the method can be right and the colour still wrong for a tree you show. Kiyonal is a 100 g bonsai tube, not a brush bottle. Reviewers say to squeeze a little from the tube or lift it with a tool, because fingers pick up more than the cut needs. The instructions are in Japanese with no English. Tubes split if you roll them hard from the middle. A liquid-volume field of 0.25 litres does not mean a large dose. The Flintronic listing that names grafting tape, ASIN B0GY8DX3NY, says you wrap a grafting membrane only after the wax has dried. Wrapping wet paste glues the tape to a sliding film. Comioke's two UK reviews point the same way as the Arbrex label: a thin layer, not a thick coat. Stop and call a tree surgeon if the trunk is split, a limb is hanging, you need a chainsaw above head height, or you were about to use a flame. A pot of sealer does not make that a DIY job.
Common questions
How thin should the coat be?
Thin enough to cover the bare wood and the edge of the bark, not to build a pad. The Arbrex retailers describe one thin coat, then a second only after the first has dried. UK reviewers who used a thick layer say the film cracked or peeled and left the wood open again. On the Comioke tub, one reviewer said a thin layer on fruit-tree cuts was enough. If you cannot see the shape of the cut under the gel, you have used too much.
What if the brush cap shoots off?
Stop. The Arbrex cap comes off when the bottle is squeezed hard, and the gel goes onto you or the ladder. Wipe the thread, press the cap back until it sits straight, and squeeze the sides gently. If the built-in brush spreads more than the cut needs, switch to a small separate brush or an old toothbrush kept for this job. Do not keep working with a cap that is only half seated.
When is a second coat allowed?
After the first coat has dried, and only as another thin film. The Arbrex sequence, repeated by J M Garden, B&Q, and Polhill, is explicit about that order. The Vividye seller says a second coat after 2 hours on deep wounds, which is a seller timing, not a lab result. A second coat does not fill a hollow or glue torn bark back on. If the first coat is still wet, wait. Wet-on-wet is how the layer becomes the thick coat that cracks.
What do I do about sap instead of a blow lamp?
Leave bleeding cuts unpainted. The Royal Horticultural Society says not to bind or paint sap flow on maple, birch, walnut, and vine, and to time the pruning so the flow is less. Retail pages that mention a blow lamp before Arbrex conflict with that advice, and the safety data sheet classes the gel as flammable because of ethanol. Do not heat the wound and do not put a flame near the bottle. Sap is messy. It is not a fire job.
Does the same method fit a bonsai tube?
The thin-coat idea carries over. The tool does not. Kiyonal is squeezed from a 100 g tube or lifted with a spatula, and reviewers say fingers take too much. The pack text is in Japanese. Do not brush a 300 g Arbrex bottle onto a small styled cut, and do not tip a bright green 500 g tub onto a show tree. A dab the size of the wound is the whole job.
When should I stop and call someone?
Stop if the trunk is split, a limb is hanging, the work needs a chainsaw or a ladder you are not set up to use, or disease is already through the crown rather than on one fresh cut. Also stop if you were about to use a flame near this gel. A sealer is a thin film on a cut you can reach safely from the ground. It does not cure silver leaf or canker already through the tree.
Related pages
Sources
Public UK sources from the research digest, last checked on 16 October 2026. Shelf prices and star lines are the amazon.co.uk figures in the display file. A listed frost line or a seller claim about disease is not a test run for this page.
- RHS: Reducing the size of a tree or shrub safely (retrieved 16 October 2026)
- RHS: Bleeding from pruning cuts (retrieved 16 October 2026)
- RHS: Silver leaf (retrieved 16 October 2026)
- RHS: Fungicides for home gardeners (retrieved 16 October 2026)
- RHS: Bacterial canker (retrieved 16 October 2026)
- Arboricultural Association: A guide to pruning (retrieved 16 October 2026)
- HSE: FAQ on pesticide product information (retrieved 16 October 2026)
- treeterms.co.uk: Wound sealant and BS 3998:2010 (retrieved 16 October 2026)