Amending the soil
The PH of my soil is 7.5. I was told I need to wait 3 months for it to be amended by adding elemental sulfur. I would like to start my vegetable garden without waiting 3 months. What do you suggest? Can I add the sulfur and plant my tomatoes soon after?
Certified GKH Gardening Expert
A pH of 6.5 is just about right for most home gardens, since most plants thrive in the 6.0 to 7.0 (slightly acidic to neutral) range.
Iron sulfate can be used to lower pH but requires six times more product than elemental sulfur. It reacts faster at 3-4 weeks than elemental sulfur but as with all the products can cause plant damage if over used.
Follow the label directions and you should be able to plant shortly after application.
Unless you are growing blueberries you should be fine at 7.5. Many soils of Midwest and Great Plains, where a lot of our food is grown, are alkaline. It is true that you need to wait 3 months before adding more sulphur or sulfate if you added some earlier this year. This is because it takes time to work; you risk over-correcting and damaging plant roots. If you have sandy soil, you can lower pH by adding several inches of sphagnum peat moss. Rain water is usually acidic so is a good choice for watering your plants. However, if you have limestone soil, the limestone will neutralize attempts to lower pH. For blueberries you may need to grow in containers or a raised bed. However, most crops will be fine at 7.5. Give it a try.