Growing Tomato

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05 Feb 24 Barbara Shaw (USA - Zone 8b climate)
What should I pretreat my soil with before I plant tomatoes . They are pretty and then they get root rot on bottom. I heard calcium . Is there anything else Thanks
20 Feb 24 jacob (USA - Zone 10a climate)
my understanding is that root rot is due to a lack of calcium, but calcium is usually plentiful in garden soil. the real issue is with inconsistent watering, meaning the plants cannot properly absorb that calcium. water more!
24 Feb 24 Celeste Archer (Australia - temperate climate)
I think you might have blossom end rot, and root rot mixed up. Blossom end rot occurs on the base of the tomato, and is caused by a lack of calcium (usually -- it could be other things that cause the calcium to be unavailable - PH, lack of water etc.). Blossom end rot causes the tomato to look deformed. Calcium added to the soil at the time of planting is usually adequate to ensure this does not happen. The calcium really needs to be added EARLY in the growing stages. You could also use egg shells -- I would grind/smash up the shells pretty good then work them into the soil of the planting hole; better yet, enrich with egg shells over the winter and early spring in anticipation of future planting. Root rot usually occurs when water sits around the roots of a plant for long periods of time -- bad drainage, excess watering, soil that holds too much water (which is really drainage). If you have proper aeration this usually doesn't happen since the air flow will whisk away excess moisture (provided it isn't a swamp at the roots). Try to create updrafts in your pots -- you want water drainage holes that do double duty -- let the water run off and allow air in. I find that holes at the SIDE BOTTOM of the pot, rather than directly under the pot, work well. It may seem like a hole at the side of the pot will let the soil out -- but pretty much after the first watering this stops happening -- and once the roots take hold it certainly does not happen. No need for drainage material (stones etc.) -- just use soil/compost top to bottom -- expect soil to come out at first when filling the pot -- after that you should be fine. I make my holes rather large -- on a BIG pot these holes are about 3inches (circular). Roots of plants really like air (maybe not direct exposure) but they certainly like the occasional breeze through the soil. Face the hole on the shady side of the pot for a cooling updraft in hot weather.
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This planting guide is a general reference intended for home gardeners. We recommend that you take into account your local conditions in making planting decisions. GardenGrow is not a farming or commercial advisory service. For specific advice, please contact your local plant suppliers, gardening groups, or agricultural department. The information on this site is presented in good faith, but we take no responsibility as to the accuracy of the information provided.
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