I'm a gardening novice and am hoping you may be able to answer my many questions or can point me in a good direction for answers. I apologize in advance for the lengthy detail to include my backstory but I hope it helps to understand my many questions. I am inquiring about the importance of soil quality used for vegetable gardens maintained in containers. Does the soil need to be the same throughout the container, and does the soil at the bottom of the container affect the quality of the vegetable growth/health even if the root system doesn't reach that far down? Also, can the material of container affect the growing conditions? My questions stem from concern over the soil and material we are using in our home garden. Last year my husband and I attempted our first container vegetable garden on our deck with varying seeds and lots of only high quality organic soil. We used barrels, ceramic pots and wooden crates for containers. The large barrels/pots were very successful with beautiful healthy vegetables (kale, basil, mint, rosemary, oregano, green onion, thyme, tomato, wild flowers) but all of the smaller pots and wooden crates barely produced anything more than slow growing seedlings which halted growth and were followed by a rash of mushrooms. I assumed then that the problem with the crates was that they were made of recycled wooden wine crates and that the integrity of the crates may have compromised the soil conditions because I noticed what appeared as black mold growing in the wood; though my husband argues that the discoloration in the wood wasn’t necessarily mold and that regardless it wouldn't affect the soil or growth/health of the plants and the mushrooms have no influence. However, because the smaller pots didn't produce any productive growth, my husband started throwing his cigarette butts in these crates. (I personally do not smoke cigarettes and place high importance in the quality of my health and environment leaning toward organic-living hence my concern.). These crates remained on our deck during the off-season because my husband wanted to recycle materials for the next growing season though I was hesitant. The next growing season has now arrived. We purchased more large barrels and reused the containers that supported successful growth last year. However, my husband has already recycled the soil from the crates and pots that were unproductive. Using this recycled soil with the cigarette butts removed, he filled the bottom of all of our barrels and pots (no crates this time around) and then topped them with new bags of high quality organic garden soil. My husband insists that the soil at the bottom has no effect on the growth or growing conditions because the root systems don’t reach that far down. Should I be concerned? Would the vegetables/herbs absorb any toxins from the bottom soil because of the cigarette butts that were previously discarded there? Would the rash of mushrooms from before have dormant spores remaining that would compromise the growing conditions? Would the “black mold” from the previous season’s crates be absorbed into the soil and also compromise the growing conditions? Is it safe to eat food grown from such conditions? Thank you for any feedback you can provide.
Garden Soil Integrity
Certified GKH Gardening Expert
I would advise composting the old plant material.
If you don't compost many cities have free sites to bring your compostable material.
Here are several articles to help you get your containers ready for planting this season.