A year in the garden never fails to teach me something new, so I'm taking some time this month to highlight 10 of the lessons learned from our most recent growing season. Each of these 10 items are either subjects that I haven't covered in other posts or updates on trials that I had started in previous seasons. If you missed parts 1 to 3 of this series from previous seasons, check them out here: Part 1, Part 2, Part 3.
Here's a list of the lessons that follow in case you're looking for something in particular.
Lesson #1 - Transplanting Crops With Taproots
Lesson #2 - Finding the Perfect Oat Spacing
Lesson #3 - Interplanting Corn and Squash
Lesson #4 - Extending Our Cabbage Storage Life
Lesson #5 - Growing Our Own Mulch
Lesson #6 - Growing Weed-Free Onions With Landscape Fabric
Lesson #7 - Creating Stale Seed Beds with Solarization
Lesson #8 - Reusing Potting Soil for Container Grown Potatoes
Lesson #9 - More Encouraging Results With No Dig Potatoes
Lesson #Â 10 - Making Lentils Work in the Home Garden
Lesson #1 - Transplanting Crops With Taproots
Lessons are repeated until they are learned, so I guess I needed a reminder of this one this year. I have experimented with transplanting carrots and parsnips in the past, but the disturbance caused to their sensitive taproots during the transplanting process lead to some seriously deformed end products. The carrots and parsnips still grow. The roots are just a mess.
This year, I had planned to do our first official trial with a standard bed of sunflowers, and to achieve perfect spacing and ideal timing for this trial, I chose to transplant the full bed of sunflowers. This works wonderfully with most crops, but I was about to learn something new about sunflowers.
The transplants looked fine at first, but a few weeks later, I started to notice significant differences in the growth of each plant. As you can see from the short video clip below, the sizes varied dramatically and the leaves of some plants were quite distorted. It only took a little more reading about sunflowers to reveal that they had a strong but apparently quite sensitive taproot. Oops!
Since the official trial was a write-off at this point and I can't stand empty space in my garden, I cleared out most of these sunflowers and transplanted a crop of beets here instead to finish the season. The few sunflowers that did remain though, were outstanding, and very popular with the bees! We'll be direct seeding all of our sunflowers from here on.
Lesson #2 - Finding the Perfect Oat Spacing
It's no secret that our overall yield from any crop depends on the plant density we use, and we've finely tuned our plant spacing for most crops already, but we're still new to growing our own oats. Therefore, some oat spacing trials are important to make sure we are getting the most food from our growing space.
The first season we grew hulless oats, we had some trouble with lodging (ie. the plants falling over before they were harvested), which was not too surprising given that I started with a pretty high seed density of 42 seeds/ft². Based on the collection of small scale grain production resources I had been reading, this was about the highest density one could use for oats, and this density gave us a decent yield of 5.82 lbs for each of our 50 ft² standard beds. I was happy with that because it was above the high end yield estimates of Sara Pitzer in her book Homegrown Whole Grains. However, the lodging was frustrating to deal with, so some spacing adjustment was needed.
This year, I planted two groups of beds with two lower densities. In the first group of 3 standard beds I used a low density seed spacing of 21 seeds/ft² and in the second group of 3 beds I used a medium density seed spacing of 31 seeds/ft². Then I watched and waited.
The beds looked a little more sparse than the previous year, but the lower density gave the plants enough space and strength to remain standing straight and tall until harvest time.
Our harvest data revealed an almost direct correlation between spacing and overall yield as shown by the bar graph below. A graph like this makes it seem like we should increase the density even more, but it's not showing us the full story. Obviously, we couldn't keep increasing the yield indefinitely just by increasing the spacing because the plants would overcrowd each other so much that the yield would soon drop...and there's still that issue of lodging at high densities. However, seeing this data does make me want to creep closer to our original spacing of 42 seeds/ft² as long as we can still avoid lodging. Seed depth, timing, and irrigation quantities can also impact lodging so we don't have all the answers for homegrown hulless oats yet. This trial just got us a little closer, and it's clear now that the ideal spacing will be somewhere between 31 and 42 seeds per square foot.
Lesson #3 - Interplanting Corn and Squash
You've likely heard of the three sisters interplanting combination of corn, beans, and squash. The idea with this interplanting is that the corn grows tall and strong so the bean vines can climb the corn and the squash sprawl around the ground covering the soil surface. In reality though, the corn will not pollinate well because it really needs to be planted in a desne cluster for good pollination, the beans will not perform great in the shade of the corn and they'll be annoying to pick amongst all that foliage, and if the timing of each planting isn't perfect the squash may just overpower both of the other crops since it's a bit of a space bully.
That's not to say that we can't take a little of inspiration from the three sisters idea and apply it to our standard beds with a more organized and productive outcome. Since winter squash can wander well beyond the borders of its 30 inch wide bed space, I will select the neighbouring crops for squash strategically. The strategy is to either get a crop in and out quickly before the squash takeover, or get a crop up into the air quickly before the squash takeover.
Sweet corn meets the criteria of a tall fast growing crop, so this year I tried growing an early crop of corn between our beds of winter squash. I knew my earliest planting and harvest dates for corn, but I wasn't sure if it could win the race for sunlight with two vigorously sprawling squash beds on either side.
The photo above shows the bed of transplanted corn amidst the sea of squash on June 20th. This is only about 3 weeks after transplanting both crops so they are growing extremely fast and it's still not clear which crop will win the race.
Eventually, I was glad to see that the corn narrowly surpass the squash in height, enough to continue growing and give us a good yield from that cramped space despite the high density and encroaching squash. There are not many other vegetable crops that could have stood tall and remained productive in this scenario.
Lesson #4 - Extending Our Cabbage Storage Life
There are a couple of quick maturing cabbage varieties that I have come to like because I can plant and harvest them quickly, and by quickly, I mean getting the crop in and out of a bed in 50 days or less. Even in our short summer, that still leaves plenty of time to grow other crops in the same bed.
The downside of these quick varieties I have learned is their storage life. We can comfortably store them in our cooler for 1-2 months, and we have been preserving a significant quantity in the form of sauerkraut as well, but it would be nice to pull a crisp head of cabbage out of our cooler in March too, and to reach that goal we needed to explore the storage potential of other varieties.
This season, we devoted some bed space to a couple of slow growing cabbage varieties known to have a longer storage life and so far we have not been disappointed. The two storage varieties we tried were Expect and Red Klimaro and the heads that we harvested at the beginning of October are still in pristine shape nearly 3 months later as I write this at the end of December. Is my excitement a little unwarranted since it's only been 3 months? Maybe, but it's already clear that their storage characteristics are far superior. Whether or not they make it all the way to March, we're already getting significantly more storage life from these different cabbage varieties. It's looking like cabbage will join the ranks of other long term storage vegetables that can last the winter in their raw state.
Lesson #5 - Growing Our Own Mulch
Mulch is the last thing that we need to produce ourselves in a city that has a surplus of grass clippings, fallen leaves, and tree prunings. However, this is not the case for everyone who is growing their own food, and I'm always interested in how our gardens can include more closed loops so that they rely less on external resources.
Our explorations into the world of small scale grain production have introduced more than just grain. We now find ourselves with a pleasant surge of straw in late summer. Straw is already a readily available mulch in our agricultural region but I usually recommend against using it in the vegetable garden because it always come with weed seeds. When we are in control of the grain harvesting process though, we can use our straw a s mulch with the confidence that it doesn't contain any unharvested grain or weed seeds.
The next consideration is how we might organize the flow of mulch so that we're not constantly shuffling all of this bulky organic matter from one plot to another. Some movement is inevitable, but ideally, we'd just be moving it small distances. That's one of the reasons why I located our fall garlic planting right next to this summer's hulless oats.
We harvested the oats by stripping them by hand and left the stalks in place, knowing that we could use the straw in the same plot in a few weeks to mulch our garlic. When the time came to mulch our garlic for the winter, I took down the oat straw with a grass whip and used a rake and tarp to move the large quantity of mulch 20 feet over to cover our garlic beds.
.
Lesson #6 - Growing Weed-Free Onions With Landscape Fabric
Onions are notoriously poor at competing with weed pressure because of their slow growth and thin tops. Several weeks after transplanting, much of the bed space is still uncovered and ready to be taken over by any weeds that germinate there. Therefore, I wondered if the the soil surface could be covered to suppress weed growth effectively while still allowing the onions to grow. An organi mulch like straw would work for this purpose, but that type of mulch takes time to find and move and it doesn't just disappear when your done with it, so I turned to landscape fabric as a quicker and more convenient solution for this application.
I have used landscape fabric to grow weed free beds of many other crops, but I was nervous about using this fabric with onions because of their high plant density and swelling bulbs. Would they become trapped within the holes of the landscape fabric? Would the fabric cause a moisture build up around the bulbs and lead to fungal problems? The only way to answer these questions was to give it a try.
I set up a simple trial with two onion beds side-by-side shown in the photo above. These beds had the same irrigation lines and irrigation schedule, the same plant spacing, and the same onion variety called Frontier. Throughout the season, I paid attention for potential differences between the two beds. The uncovered bed did require a bit more labour because of the weeding time, but weed pressure isn't much trouble in this plot isn't much trouble after several years of proper management. I also anticipated possible differences in growth rate or harvest timing.
In the end, the onion tops in both beds fell at about the same time, so I harvested both beds on the same day for the sake of controlling as many variables as possible in the trial. I hung all onions to cure and took careful measurements after curing. From the uncovered bed, the onions had an average diameter of 2.86 inches and average mass of 182 grams. The bed with landscape fabric produced onions with an average diameter of 2.72 inches and an average mass of 164 grams. Based on these numbers, the growing conditions in the covered bed resulted in a 10% decrease in total yield. Now this simple trial has a small sample size and only tested one onion variety, but it seems to indicate to us that the use of landscape fabric with an onion crop doesn't seriously hinder the total yield. Therefore, when faced with growing onions in soil with a lot of weed pressure, I would definitely recommend this strategy if you'd like to keep your weeding labour to a minimum.
Lesson #7 - Creating Stale Seed Beds with Solarization
Carrots may be the trickiest crop to grow while also avoiding weed pressure, but its still possible. The solution is not to spend more time pulling weeds. That's only a last resort. Ideally, we want to avoid germinating all of those weed seeds in the first place or efficiently kill all of the weeds present before planting the carrots. One method that accomplishes this goal is to create a stale seed bed with solarization. The video below demonstrates the process so I'll skip the explanation and let you watch that.
The resulting beds were a pleasure to tend this summer. I might have reached down to pull 6 weeds for the entire time the carrots were in the beds, and I'm not exaggerating. It was idyllic! I will remind you though, that I've been managing the soil at this plot with weed preventing techniques for 6 years already. The work I've done in those previous years will have also contributed to the success of this solarization technique. To see more examples of weed controlling techniques that we use in our gardens check out this video on YouTube.
Lesson #8 - Reusing Potting Soil for Container Grown Potatoes
Last year, we did a controlled trial with two varieties of container grown potatoes. You can read more about that here. In short, the containers were reasonably productive, but came with significantly more work and cost compared to field grown potatoes. The largest annual cost of container grown potatoes is the potting soil, so I wondered if we could reduce that cost at all be reusing our potting soil for multiple seasons. Would we observe a decrease in yield? Would we have disease problems? The only way to really know was to give it a try, so with some admittedly lowered expectations, I set out to grow another round of potatoes in containers, but this time with the very same potting soil we had used the previous season. I didn't even top it up with fertilizer.
I used two potato varieties each year, but only the Bellanita variety was used both years so we'll use the Bellanita data only for comparison. In 2022, our 5 plastic containers of Bellanita potatoes yielded 33.4 lbs and our 5 fabric containers of Bellanita potatoes yielded 25.2 lbs. In 2023, our 5 plastic containers of Bellanita potatoes yielded 20.2 lbs and our 5 fabric containers of Bellanita potatoes yielded 13.2 lbs. Our total yield decreased from 58.6 lbs to 33.2 lbs. That's a remarkable 43% loss in yield. Now, there were a couple of variables that I didn't control precisely, such as the sun exposure and irrigation, but the planting method was the same, the containers were identical, and the pots were irrigated with the same drip system both years. Minor differences with those variables shouldn't have amounted to a 43 % loss in yield so I will attribute much of that difference to the reuse of the potting soil. While this is a little disappointing, it may not mean that we need to dispose of the potting soil altogether. Perhaps a refurbishing of the potting mix would be possible with a top up of organic fertilizers. That's an experiment for another time though.
Lesson #9 - More Encouraging Results With No Dig Potatoes
The initial trial we did with no dig potatoes compared this growing method with no till and double dig methods of bed preparation. You can learn more about that initial trial here. What was surprising then, was that the two potato varieties responded differently to the different growing methods. That left me curious to try no dig trials with additional potato varieties.
In 2022, I set up another well controlled trial with Red Sangre potatoes to again compare the no dig method with the no till method. I measured out the same number and mass of Red Sangre seed potatoes to plant in two separate 50 ft² beds. The only difference was that one bed was planted in the no dig style, with seed potatoes placed on the surface and covered with a thick layer of mulch, and the other bed was planted in the no till style, with seed potatoes deposited in a 4-6 inch deep holes before filling the holes in with soil.
The results of this trial were really encouraging for the no dig method. We harvested a total of 38.2kg (84.0 lbs) from the no dig bed and 39.0 kg (85.8 lbs) of potatoes from the no till bed. That difference in yield is not significant enough to justify using the no till method to optimize yield, especially considering how much more labour is required to harvest no till potatoes. To see just how easy it is to harvest no dig potatoes, check out this short video showing a few clips from the harvest of our 2023 no dig potato beds.
Lesson # 10 - Making Lentils Work in the Home Garden
Since we're self-sufficient in most vegetable crops now, I can't help but expand our crop selection further to include foods that are typically found in the home garden. One of the crops we added this season was lentils.
You likely won't find lentils in your favourite garden seed catalog, but I was able to find lentil seed in the bulk bins at our local organic grocer. I selected a large green variety called Laird lentils here in Saskatchewan, and I was able to seed them easily with the use of our Earthway seeder. This mechanical seeder opens a trench, deposits seed, and closes the trench as you roll it along the bed surface. The seed quantity and spacing can be controlled with the selection of different seed plates that mount inside the red hopper.
The seeding of the lentils was never the part that worried me though. It was the harvesting and threshing process that came with the most questions, so again, I found myself watching and waiting. I could only guess what kind of new harvesting routine I might need for this crop, but at least I knew that I had our homebuilt threshing machine to help with the process.
What happened next is mostly described in the short video below, so I'll spare you the reading and let you just watch that. While the first round of lentil harvesting wasn't without it's mistakes, it proved to be straightforward enough for us to repeat the process again in the seasons to come. The yield also didn't disappoint. When the threshing was all wrapped up we had 3.56kg or 7.83 lbs of lentils. There was some loss in the drying and threshing process this time around, so I’m confident we can beat those numbers next season. For now, it’s just nice to have a benchmark to use for our production estimates going forward. If you’re curious how these harvest numbers compare to large scale agriculture, average yield for large green lentils in our province is 1546 lbs/acre. Our yield from this 100 square foot test plot equates to 3412 lbs/acre.
That's where we'll end this round of lessons. I hope you picked up a few practical tips from these shared experiences, but more importantly, I hope this post encouraged you to take more control as a gardener. Many of these stories are examples of times when I had no answers for my questions, so I had to use my own research, trials, and observations to determine the best direction forward. Ultimately, you need to take charge of the things that are happening in your garden, and sometimes that means figuring out the best solution yourself. That said, I have been doing trials like this for a decade already and I have to admit it does take a lot of extra time. If you'd like to benefit from all I've learned and take the fast track my Seed to Table course has everything you need. To learn more about this course and our growing methods, get started with my Free Workshop.