RHS Gardening Advice
March 2018

 
Inclusion of a fungicide product on this page does not indicate a recommendation or endorsement by the RHS. This is a list of products available to the home gardener.

Introduction

Some diseases can be controlled by several different fungicides. The effectiveness of some fungicides may depend on the environmental conditions, so gardeners may need to try more than one to find those that give the best control of the diseases which affect their plants. Regular use of certain fungicides may lead to the build-up of strains of fungi which are tolerant to them so that they will cease to be effective. It is important not to make more than the recommended number of applications of a particular active ingredient in any one year.

All garden chemicals on sale in the United Kingdom are safe when used according to the manufacturers' instructions. Every proprietary product has been issued with a DEFRA or MAPP (Ministerially Approved Pesticide Products) number found on the pack.
 

For the most effective and safe use of fungicides, rules should be observed:

  1. Use chemicals only when they are really necessary. Prevention is invariably better than cure and many diseases can be kept down by cultivation techniques such as rotation of crops, destruction of crop residues, thorough digging, drainage of heavy soils and good tool hygiene.

  2. You must select a chemical which is recommended for the particular purpose you have in mind. It is good practise to check the label before choosing a product.

  3. Always read the manufacturers’ label and check for any limitations or specific precautions you should take. As an added precaution you could wear rubber gloves, particularly when handling the concentrate or when spraying.

  4. Follow all the instructions on the manufacturer's label and apply the

  5. chemical at the stated rate and in the manner described. It is a legal requirement to comply with the Statutory Conditions indicated on the label.

  6. Make sure that you are spraying at the correct times and intervals, as this is often crucial for the control of a disease.

  7. It is illegal to mix two chemicals together to give a combined spray unless this is recommended on the label or leaflet.

  8. Note: where a proprietary product contains an insecticide as well as a fungicide it would be preferable to use an alternative product if pests have not been a problem on the plants treated.

  9. Avoid contact with exposed parts of the body, particularly the eyes. Wash off any splashes immediately with clean water.

  10. Avoid breathing in dusts or sprays. Wash after using sprays or dusts.

  11. Make sure no children or animals are in the vicinity when spraying.

  12. Do not smoke, eat or drink while spraying.

  13. Spray efficiently to wet the plants without excessive run-off or drift, but thoroughly wet the stems, buds and the underside as well as the upper surface of the leaves.

  14. Do not spray or dust in windy, completely calm or hot sunny weather. Spray in the early morning or late afternoon or evening.

  15. Do not spray plants which may be injured by the chemical or allow spray to drift on to them. Because of the large numbers of species and varieties of ornamental plants grown in gardens, sensitivity to products should always be checked on a small area or number of plants in the first instance.

  16. Clean all equipment after spraying.

  17. DO NOT apply fungicides with apparatus that has been used for weed killers.

  18. Always try to make up only sufficient solution for the task. Left-over spray must not be poured down the drain

  19. Store chemicals in a cool, dry, frost-free, safe place away from children and pets, keeping them tightly closed and in their original containers.

 


Choosing fungicides available to home gardeners

The following list has been drawn up to aid members of the Society in choosing fungicides. Most of the fungicides available to home gardeners are ideal garden chemicals in that they are cheap, effective and safe to use when applied as directed on the label. However, always take note of any usage limitations given for the fungicides in this list.

Proprietary products sold for the control of plant diseases are listed under the common chemical names of their active ingredients in alphabetical order. All manufacturers are obliged by law to print the name of the active ingredient on the label, but this may appear in very small print.
 
Please note that inclusion does not indicate a recommendation by the RHS for the uses specified on the product. It must also be emphasised that the RHS is not liable in any way for any consequences which may ensue from the use of fungicides by home gardeners.
 
Some fungicide products listed in this leaflet under their manufacturers’ names may be available from retail outlets as “own brand” products with the retailers’ own labelling. It is not practical to list all of these. Check the label of the crop protection product carefully to confirm the active ingredient.
 


Products available to home gardeners

1. Myclobutanil
Systemic fungicide to control rust, black spot and powdery mildew on roses; rust and powdery mildew on ornamentals.

 
Active Ingredient Proprietary Name Manufacturer / Source of Supply Formulation
Myclobutanil and cypermethrin* Multirose2 Bug Killer and Disease Control SBM Life Science Ltd ready-to-use spray
Myclobutanil and cypermethrin* Resolva Rose 3 in 1 Westland Horticulture Ltd ready-to-use spray
Myclobutanil and cypermethrin* Rose Shield Bug & Fungus Killer Doff Portland Ltd ready-to-use spray
Myclobutanil and cypermethrin* Rosegarde Vitax ready-to-use spray
* with cypermethrin for insect control. Only for use on ornamental plants.

 
2. Protective seals on pruning wounds
Used to form a protective seal, with no curative action, on trees and shrubs after pruning or wounding.

 
Active Ingredient Proprietary Name Manufacturer / Source of Supply Formulation
Octane acid (iron and sodium salts) Growing Success
Prune and Seal
Westland Horticulture Ltd ready-to-use liquid
Natural resin Solabiol Arbrex Seal and Heal SBM Life Science Ltd ready-to-use
Natural resin Medo Vitax Ltd ready-to-use
Natural resin Prune and Seal Neudorff UK Ltd ready-to-use

 

3. Compounds with a physical mode of action


Products containing a blend of surfactants and nutrients to control some pests and disease by a sticking and washing process. They can be used on all edible and ornamental plants and there is no harvest interval. May be used against powdery mildew and a range of pests including, whitefly, aphid, spider mite, mealy bugs, scale and psyllids.
 

Active Ingredient Proprietary Name Manufacturer / Source of Supply Formulation
Physical mode SB Plant Invigorator Stan Brouard Ltd liquid concentrate
Physical mode Resolva Natural Power Bug and Mildew Westland Horticulture Ltd ready-to-use spray
Physical mode Rose Defender RTU Ecofective ready-to-use spray
Physical mode Rose Defender Concentrate Ecofective liquid concentrate
Physical mode Houseplant Defender Ecofective ready-to-use
Physical mode Bug & Mildew Control Ecofective ready-to-use
 

4. Tar acids and oils

Tar acids and tar oils are derivatives of coal tar. Formulations are available as liquids or pastes for disinfecting tools or surfaces.

Limitations: Should be kept off the skin and away from eyes, food and food containers. Hazardous to fish. Protective gloves, for example neoprene (not natural rubber) and goggles should be worn when handling the concentrated disinfectants.

 
Active Ingredient Proprietary Name Manufacturer / Source of Supply Formulation
Tar acids and oils Jeyes Fluid Jeyes UK liquid concentrate
Tar acids and oils Jeyes Fluid Jeyes UK ready-to-use spray
 
Please note: these products are no longer labelled for pesticide use, but are available for the disinfection of greenhouse structures, seed trays and pots.
 

5. Tebuconazole

Tebuconazole is a systemic fungicide to control blackspot, box blight (Fungus Fighter Concentrate), powdery mildew and rust on roses and other ornamental plants. Tebuconazole and Trifloxystrobin (also a systemic fungicide) are combined in ‘Fungus Fighter Plus’ to control diseases on roses and other ornamental plants including blackspot, powdery mildew, rust and leaf spots, box blight and white rust. Fungus Fighter Plus also controls powdery mildew on glasshouse crops of cucumber, courgette and summer squash.

 
Active Ingredient Proprietary Name Manufacturer / Source of Supply Formulation
Tebuconazole and deltamethrin* Multirose Concentrate2 SBM Life Science Ltd liquid concentrate
Tebuconazole Fungus Fighter Concentrate SBM Life Science Ltd liquid concentrate
Tebuconazole and Trifloxystrobin Fungus Fighter Plus SBM Life Science Ltd ready-to-use spray
Tebuconazole and Trifloxystrobin Toprose Fungus Control & Protect SBM Life Science Ltd ready-to-use spray
* with deltamethrin to control insect pests.
 

6. Trifloxystrobin

Protects lawn against lawn diseases such as Fusarium patch and red thread.

Active Ingredient Proprietary Name Manufacturer / Source of Supply Formulation
Trifloxystrobin Lawn Disease Control SBM Life Science Ltd soluble powder

 

7. Triticonazole

Systemic fungicide to control blackspot, powdery mildew and rust on roses and ornamental plants.

 
Active Ingredient Proprietary Name Manufacturer / Source of Supply Formulation
Triticonazole Fungus Clear Ultra Scotts Company
(UK) Ltd
liquid concentrate
Triticonazole Fungus Clear Ultra Gun Scotts Company
(UK) Ltd
ready-to-use spray
Triticonazole and acetamiprid* Roseclear Ultra Scotts Company
(UK) Ltd
liquid concentrate
Triticonazole and acetamiprid* Roseclear Ultra Gun Scotts Company
(UK) Ltd
ready-to-use spray
* with acetamiprid to control insect pests.
 

 

ALWAYS READ THE LABEL
USE PESTICIDES SAFELY

 

Manufacturers/Distributors

 
Company Name Address Telephone
Bayer See SBM Life Science Ltd  
Doff Portland Ltd Aerial Way, Watnall Road, Hucknall, Nottingham NG15 6DW 0115 963 2842
Ecofective 4 Archway House, Melbourn Street, Royston, Hertfordshire, SG8 7BX 01763 212103
Jeyes Groups Ltd Tennyson House, Brunel Way, Thetford, Norfolk  IP24 1HF 01842 757575
Neudorff UK Vienna House, Birmingham, International Park, Solihul, B37 7GN 0121 7671821
SBM Life Science Ltd  Unit 2, Tech+no Park, Newmarket Road , Cambridge CB5 8PB 0845 345 4100
Scotts Company (UK) Ltd 1 Archipelago, Lyon Way, Frimley, Surrey, GU16 7ER 01276 401300
Stan Brouard Ltd PO Box 383, Landes du Marche, Vale, Guernsey GY1 3FE 01481 252521
Vitax Ltd Owen Street, Coalville, Leicestershire LE67 3DE 01530 510060
Westland Horticulture Ltd Alconbury Hill, Huntingdon, Cambridgeshire PE28 4HY 01480 443789

 


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