Scotts Lawn Builder +Weedkill Slow Release Lawn Fertiliser

Scotts Lawn Builder +Weedkill Slow Release Lawn Fertiliser

Size: 4kg

Main product features

Kills weeds not lawns
Kills weeds not lawns
Feeds for up to 3 months
Feeds for up to 3 months
Thicker lawn
Thicker lawn
No scorch formula
No scorch formula

This popular lawn fertiliser has an excellent reputation with home gardeners and professional turf managers alike. The 'set and forget' solution to having a great lawn all year round, this product includes selective herbicides that will kill most broadleaf weeds with exceptions

When to use



  • Weedkill contains three selective broadleaf herbicides that will control a broad range of weeds (see technical details below for a list)
  • Boosted iron and sulphur content promotes deeper green and stronger growth. The thicker the lawn, the less chance weeds have of taking hold - they're smothered before they become obvious and need treatment
  • Slow-release of nutrients through controlled feeding eliminates waste through run-off and leaching and prevents burning and surge growth
  • Traditional lawn foods release or 'dump' most of their nutrients within a couple of weeks of application, causing a rapid surge in growth that quickly drops off again as the food supply diminishes. Scotts Lawn Builderâ„¢ uses patented time-release technology to ensure nutrients are released slowly and continuously over a three month period
  • Weedkill has a low 1% phosphorus, which means it can be safely used anywhere in New Zealand without posing any risk to ground or surface water
  • The recommended low application rate is just 16 grams per m2, not the kilograms often associated with regular lawn foods!



  • Weedkill can be safely used on lawns containing common couch, bent (not on bent greens), kikuyu, perennial ryegrass and/or Chewings fescue ONLY



  • DO NOT USE on buffalo, carpet grass, lippia, dichondra or Santa Ana couch as these grasses and lawn substitutes may be damaged by this product. This includes all named varieties of buffalo - Sir Walter, Palmetto, Sapphire, etc
  • DO NOT lay new grass or sow patching products within one month of application
  • Do not apply on or around food plants or animal feed crops
  • Do not use on new lawns until at least 4 weeks after the first mowing
  • Do not use if the temperature is expected to exceed 30 degrees C - wait for a cool spell

CAUTION: Keep out of reach of children.

Read Safety Directions before opening or using.


  • Weedkill is a slow-release fertiliser that provides continuous nutrition over a three month period while eradicating selected broadleaf weeds
  • Every granule of Weedkill contains Scotts patented time-release nitrogen
  • Nutrients are released at about the same rate that grass roots can take up the fertiliser so there is no wastage, run-off to waterways or damaging surge growth


How much will I need?

Weedkill has a recommended application rate of 16g/m2

To work out how much you will need to fertilise your lawn:

  1. Calculate the area of the lawn in square metres (multiply the length by the width)
  2. The area multiplied by the application rate will give the exact amount of Scotts Lawn Builder you need
  3. Use a set of scales to weigh it out and then add it to the spreader ready to apply - do not be tempted to add a 'bit extra for luck' because over-application may result in nitrogen burning
As a Guide m2
1/4 Tennis court 65
1/2 Tennis court 130
Full Tennis court 260

How do I apply it?

  1. For best results ALWAYS use a Scotts spreader
  2. Check your model and make sure to set it correctly before you start (settings are also on the back label of the product)
  3. If you don't have a spreader, make sure you distribute the fertiliser evenly over the lawn - uneven applications may result in 'hot spot' burning where too much has landed in one spot
  4. Don't attempt to cover the area in one pass - you may under or over apply. Even coverage may be better obtained by passing over the entire area at least three times, moving at a different angle and applying about one third of the total amount in each pass
  5. Apply to moist foliage. If the lawn is not moist from dew or recent rain, wet the area to be treated
  6. Allow the product to remain undisturbed on the lawn for 24 hours before watering in thoroughly
  7. Rain, watering or heavy foot traffic within 24 hours can knock granules off weeds and may reduce the effectiveness of the weedicides
  8. Do not mow within 48 hours of applying this product
Type Spreader Setting
EvenGreen Drop Spreader 5
EasyGreen Rotary Spreader 26
HeandyGreen Easy Handheld Spreader 4 1/4

For a complete guide on How to Use Scotts Lawn Builder + Weedkill Slow Release Lawn Fertiliser, watch the video on this page and always check the packaging


Recommended Application Times & Weeds Controlled:

Autumn to Early Spring Bindii (Onehunga Weed), Capeweed, Catsear (Flatweed), Chickweed, Dandelion, Fumitory, Hydrocotyl (Pennyweed), Mallow, Mouse-eared Chickweed, Plantain (Lambs Tongue)
Spring & Summer Cobblers Peg, Creeping Oxalis, Chickweed, Dandelion, Hydrocotyl (Pennyweed), Plantain, Fat Hen, Catsear (Flatweed)
Year Round Clover, Pearlwort, Staggerweed, Wireweed. Best control will be gained when weeds are actively growing and young, rather than when they are flowering or seeding
  • Do not apply if weeds are stressed due to dry, frosty or excessively moist conditions
  • Do not apply if rain or irrigation is expected within 24 hours
  • Avoid applying when daytime temperatures are forecast to exceed 30 degrees
  • Do not re-apply for at least 10 weeks after initial use


IMPORTANT: This product, when wet, will cause iron stains. Be sure to sweep all granules off paths, coping, paving, driveways, shoes, etc immediately after use. Do not allow the granules to come into contact with these surfaces when they are wet.

Store safely out of the reach of children and pets. This product contains iron which can be harmful to dogs' livers if eaten in quantity. It also includes herbicides which may be dangerous.


DO NOT allow granules to come in contact with or drift on to plants you do not want killed, such as shrubs, flower beds and vegetable gardens. Grapevines and tomatoes are particularly sensitive to this product

DO NOT allow containers or granules to get into drains, sewers, streams or ponds

DO NOT feed grass clippings from treated areas to poultry or other animals

This product is harmful to aquatic organisms and very toxic to some plant species (it will kill them)

SAFETY FIRST: Read the instructions on the product packaging before use and take particular note of any warnings or cautions on the label


NPK 20 : 1 : 15

Herbicide active constituents are 2,4-D, mecoprop and dicamba acid

Feeds for 3 months without burning when used as directed and applied at no higher than the rate recommended on the bag

Includes Scotts patented time-release nitrogen and potassium formulated to release nutrients as your lawn needs them

Health and Safety

Always read the pack label and product instructions carefully before use. For further information relating to product safety please review the product data safety sheet link below.

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