Questions answered by Pip staff
AFTER THE FLOODS
Much of Australia’s eastern seaboard has experienced devastating floods over recents months. And while most of us are all too aware of the work required to clean, restore and even rebuild homes and buildings, Pip has received plenty of questions about the impact floods can have on our plants, soils, food crops and animals.
Some of my plants look like they might not recover after they experienced flooding. Is there anything I can do to save my favourites?
Unfortunately, no. As well as nutrients, healthy soil is providing the roots of your plants with oxygen through air pockets within the soil structure. But once soil has been immersed in water for any period of time, all of the air and oxygen is forced out and the root system begins to wilt and die. As well as any unknown contaminants that may have moved into your yard with the floodwaters, the roots systems will not recover, so you’ll need to remove all of the plants and start again.
A friend advised me not to eat anything from my garden due to the toxins that may be present in the floodwaters. Is this right?
Spot on. Floodwaters will be full of all sorts of contaminants. Things like garbage, sewage, chemicals, building toxins, asbestos and industrial pollutants could be present. Even though this may not be the case, it’s important to eliminate any risk by not consuming any edible plants that have come into contact with floodwater.
There’s a layer of silt which has settled over my yard and garden after the floods. Can I dig it into the ground before I start again?
No. As well as the likelihood of heavy rain washing away the topsoil you’ve lovingly built up, the fine silt that’s left after the water recedes needs to be removed, too. The main reason for this is you just don’t know where it has come from and what it contains. Water picks up anything in its path and the likelihood of toxins being present is very high. Get rid of it as soon as you can though, the longer you leave it, the harder it becomes – literally. It’s a good idea to wear gumboots and gloves while removing the fine layer of muddy silt, too, to reduce any risk of infections or coming into contact with soil-borne diseases.
I’ve spent the last couple of years building up my soils with compost and other organic matter, but my garden has been underwater due to the flooding. Can I plant back into it once the water recedes?
Once you’ve removed the layer of toxic silt, you need to set about trying to get oxygen back into the soil to bring it back to life. Add as much organic matter as you can, but if your homemade compost also suffered the same fate, you can dig some coarse mulch into your garden for structure and to allow the air and oxygen to recirculate. Pine bark mulch should be readily available, but be aware that waterlogged soil will be suffering from nitrogen deficiency, and as pine bark breaks down, it’ll be taking more nitrogen with it, so one handful of pelletised chicken manure per square metre will help. Waterlogged soils are likely to be acidic, too, so adding a handful of garden lime per square metre as you go will help stabilise this.
Cover with a layer of sheet mulch for a month or two to encourage the worms to come in and do some more cleaning up for you. Depending on the severity of your flooding, it would be a good idea to conduct a soil test before you begin growing food, just to be sure it’s where it needs to be. Check out the info about VegeSafe soil tests on page 8.
My chicken coop was flooded. I managed to get my girls out in time, but is there anything I need to do to coop before they go back in?
Remove any soggy bedding materials and, if made from timber, make sure it’s dry (use fans if you need to) before reintroducing them back in. For the reasons outlined above, remove the silt layer as best you can and cover the ground with a thick layer of straw – if the ground is really muddy and taking a long time to dry out, think about putting some pallets down as well, so their feet aren’t always wet.