I have a Sir Walter Lawn but in very sandy soul at Maroochydore this it dries out so quickly. Bunnies NGOs sell a Hortico brand of water retaining crystals. I have a few questions if someone could answer them that would be great. 1/ Are they safe for pets etc.
2/ Do they work. 3/ how much do I need for 100m2 of lawn.
Welcome to the Bunnings Workshop community @aussieagent. It's fantastic to have you join us and many thanks for your question.
You should place water storage crystals within the roots zone of a plant. It would be difficult to dig them in deep enough to be effective as your grass is already established. Instead, I would suggest you topdress your lawn several times over the next couple of years. This will add organic matter to the ground and raise the height of the root level. You can apply some storage crystals before top dressing. The crystals are non-toxic and biodegradable. Once applied, there should be no issues with pets.
For 100 square meters, I would suggest purchasing EDEN 1kg Water Storage Crystals as they will be the most cost-effective option. You will use most of this container over that area.