Gardening in Pots Part 3 - Lessons Learned So Far
In the two previous posts, we explained why we decided to build a big container garden (or, as one of our volunteers calls it, the pot garden - just not that kind of pot garden) and how we built it. Once we added plants and irrigation, we found we had a lot more to learn!
Big container gardens require many hands to build - We used about ten cubic yards of super soil to fill about 700 to 800 pots. Many volunteers - from scouts to airmen to Master Gardeners to weekly volunteers - moved a tremendous amount of soil from pile to pot. If you’re considering a large container garden project, give yourself time and recruit some help. Once the pots are filled and planted, the area can be managed by fewer people.
Visitors explore the new container garden.
Buy soil in the fall - By March, everyone in the River Region was starting a garden, and the quantity and quality of the soil mixes we bought decreased. Some days, we couldn’t find soil at all. If you start a garden in the fall or just buy your soil and keep it covered until spring, you’ll have better quality soil.
Buy the biggest pots you can - Just a reminder from the last post, don’t waste your money on 1 to 5 gallon pots. Buy bigger pots, and you’ll have better results. You can also reuse cow mineral tubs, old buckets or nursery pots. Just make sure to add drainage holes if they don’t already have them.
Handles are important - Make sure your fabric pots have heavy duty reinforced hands handles. (Some pots have no handles, and you really need the handles.) When you are carrying 10, 15, 20 pounds of dirt, sturdy, reinforced handles are important. We’re starting our third season with the pots, and we haven’t lost a handle, yet.
Fertilize often - In a container, what you’ve got is all you’ve got. Roots can’t travel far to find nutrients so your job is to supply the plant with nutrients throughout the growing season. We are still determining the best schedule, but we have tried adding slow release organic fertilizer (Mighty Grow, which is no longer available), one to two ounces every two weeks along with soil drenches of diluted liquid fish fertilizer every two or three weeks, too. We still need to experiment with foliar feeding, spraying fertilizer on the plants’ leaves.
Bottle gourd or any sprawling climbing plant needs lots of water and fertilizer.
Water, water, water, water - The soil in fabric pots dries out more quickly than soil in plastic pots. That can be beneficial if we’re having a really wet season, or it can be a challenge to make sure the plants have enough water. The overhead sprinkler was convenient (and easy to find locally). It did a good job soaking the soil in the entire pot, but it waters the paths as well as the plants. The spot spitters in the drip system put water directly into the pots, but the water flowed straight through rather than soaking into the pot. Even with the spot spitters, we still ended up with rivers of water flowing down the plastic paths.
As we transition from summer to fall plants, we will try to manage the water better by 1) making sure there is more compost in the soil mix. After a season of growth, the soil in the pots is mostly sand. Adding ½ to ⅔ compost to ½ to ⅓ sand per pot may help the pots hold more water. 2) decrease the pressure on the irrigation system even more. We chose a medium flow spot spitter. In the future, we’ll test the low flow spitters, but until then, we’ll decrease the flow of the whole system by turning the faucet down.
A ½ inch is not a ½ inch is not a ½ inch - The most frustrating lesson we learned was that every irrigation supplier has a different idea of what ½ inch means. The diameter of one pipe was different than others and some fittings worked and some wouldn’t slide on the pipes to save our lives. We pieced together different solutions and made it work, but the time and money spent making something out of mis-matched pieces was irritating. Buy your irrigation supplies from the same place.
Peppers and basil thrived - Both our hot and sweet peppers produced well from May until today. Our hot pepper varieties were buena mulata, fish, and early jalapeno. Our sweet pepper varieties were aura, corno di toro, California wonder, purple beauty. The purple beauty did not produce very large peppers in the pots or in the raised bed garden so we probably won’t grow that variety again anywhere.
For basil, the majority of the plants were a compact and fusarium wilt resistant variety called elidia. As long as it was watered and picked, it kept producing bags and bags of basil.
Other summer vegetables we tried were eggplant and an edible gourd. Flea beetles plagued the container eggplant all summer, but not the one we planted in the culverts by the greenhouse. Of the varieties, the long slender Asian eggplant managed much better than the round varieties. Overall, though, none of the eggplant did that well.
Summer interns and volunteers harvesting hot peppers.
The bottle gourd or lau needed much more water and fertilizer than it got. The lau appreciated weekly diluted fish emulsion drenches and lots of water. Gourds and old winter squash varieties send out long runners that root in different places for water and nutrients. It’s hard for the pots to provide what these plants need.
Plant for pollinators, too - We also grew marigolds and holy basil in the container garden because they are lovely plants, and because they attract pollinators. Keep space (and pots) for pollinators, too. (Letting some basil flower is another way of encouraging pollinators to visit your garden.)
Pests & problems in containers - Flea beetles followed by leaf footed bugs were the main garden pests. The flea beetles focused on the eggplant, peppering the leaves with tiny holes. Flea beetles also damaged the cabbage and chard we planted in the spring. Next year, we will keep spraying the leaves with Surround, an organic clay mixture that keeps pests from damaging plants. The garden definitely needs a flea beetle strategy.
Leaf footed bugs, sometimes called stink bugs, found the pepper plants in August. They damaged peppers and tomatoes by biting them and making them taste funny. They did not affect too many peppers, and like the tomatoes better. Because they are fast flyers and avoid sprays, we catch and squash as many as possible or cut them in half with clippers.
We anticipate that frequent use of the pots might allow fungal diseases or plant viruses to linger in the fabric as well as the reused soil. We could solarize the pots using clear plastic or even wash them. We’ll let you know.
So this is just a brief (ha, ha!) summary of what we’ve learned so far in the container garden. We are always learning things on the farm, and will keep you posted as our adventures in pots continue.