One of the exciting parts about growing your own food is that no two growing seasons are ever the same. For starters, there is always some variation in temperature, precipitation, and pest pressure. Add to that a few new experiments on our part, and we are guaranteed to learn something new each year. Here is a breakdown of the 10 biggest lessons from our 2018 growing season.
Lesson #10 - Securing Our Year Round Carrot Supply
In 2017, I grew our earliest carrots ever after trying some new techniques to speed up germination in early spring. This spring, I worried that my 2017 results would not be repeatable on account of a winter that just wouldn’t end here. (ie. snow cover until late April) It occurred to me then that I might have just gotten lucky with some warm weather the year before. However, with attention to the same basic principles that gave me success in 2017, lo and behold, we were once again harvesting full sized carrots in June as shown in the photos above. What was especially exciting about this early crop is that we still had carrots from 2016 in storage when we started digging our 2017 crop. That means, we had successfully grown a year round carrot supply for our family in our zone 3 climate. I love carrots so this goal has been on the wish list for some time. The bar has officially been raised and I will now look forward to repeating this for many years to come. . For all the details on how we get our carrots off to an early start, see this How to Grow the Earliest Carrots post in our Classroom.
Lesson #9 - A Serious Introduction to Common Potato Scab
I felt persuaded by another grower in our area to try growing potatoes with minimal irrigation this season. Water costs are high in the city and potato seed generally has enough energy and vigour to get off to a good start without any babying. I predicted somewhat lower yields and still watered during the tuber formation phase to help the roots bulk up, but I still ran into trouble. Call it a perfect storm, or lack of storm, if you will, since this experiment coincided with the driest summer I can remember here. The lesson learned after the fact, was that the soil bacteria known as common scab really thrives in these dry years. The combination of my dry land growing experiment and the lack of rain created perfect scab conditions. It’s painful to dig up your potato crop only to find it overcome with scab so we’ll certainly be taking more precautions next season. The scabby lesions are caused by a bacteria called Streptomyces scabies which lives in the soil. Dry soils with a high pH and lots of organic matter will promote the growth and infection of this bacteria. The scab doesn’t affect yields or the quality of the inner tuber. The scabby potato skin just ruins the appearance. While I am not about to stop adding quality composted organic matter to our plots, I can definitely make a point of irrigating our potato crop regularly. I can also make choices in the planning stage by choosing more scab resistant varieties to grow and planning to grow them in different locations every season. Even in this dry year, we noticed big differences in the ability of our potato varieties to resist scab, so it is worth selecting seed carefully.
Lesson #8 - Starting Spinach in the Heat of Summer
Most people in our area plant spinach in the early spring, harvest it until it bolts, then wait a whole year to grow it again. We could extend this harvest window a little by planting a few successions of spinach in spring, but we are interested in stretching this even further, so we have been experimenting with ways to grow it later in the summer. . Since spinach seed prefers cool temperatures for optimum germination, this is the major challenge when planting in during warmer months. There is no cool soil to be found in mid summer. . To get around the germination problem this year, I tried starting spinach as transplants. I started multiple seeds in each soil block to help with efficiency and let them germinate for 5 days in one of our refrigerators. The germination rates were perfect! Once hardened off, the clumps of baby spinach plants were transplanted out into the field. More experimentation is needed to refine the spacing, but we will definitely be repeating this on account of the success this season. . For more photos and specific details about this process, check out this post in our Classroom: Two Methods for Starting Spinach in the Heat of Summer.
Lesson #7 - Parsnips Need Their Space
After a few frustrating experiences with parsnips in previous years, I decided to give them more attention this season. My mistake in the past had been to treat them too much like carrots. Yes, they are closely related and even look the same, but their needs are still unique. Parsnip foliage is much thicker blocking out a lot more light than wispy carrot leaves. (Photo 2) The ideal parsnip root in my mind is also significantly larger than the ideal carrot. (See photo 3 for a carrot parsnip comparison.) For both of these reasons, it seems logical that a parsnip plant would demand more space than a carrot, in hindsight. I had given them a little more space than our carrots before, but I still found myself digging up loads of long, stringy roots even after a long growing season. . This year, I switched to using pelleted seed, which helped with germination consistency and also made it easier to seed the parsnips with even spacing. We also thinned the plants to one every 4 inches in their rows. It’s counter intuitive that you could pull out some of your plants and still end up with a bigger harvest, but in this case that seems to be the case. Too many parsnip plants just can’t compete with each other. A low plant density, on the other hand, allows each plant to fully mature and makes all of the digging labour much more worthwhile. Parsnips are a challenge to dig out whether they are long and skinny or long and fat, so I’d much rather pull out fewer fat ones. They store better too.
Lesson #6 - The Best Offense Is A Good Defense
I’m sure you’ve heard it before, but some lessons need repeating. In our case, we were reminded of this lesson with our patch of Rainbow chard. I love growing chard for many reasons that I won’t get into now, but in our part of the world it does have one point of weakness. Chard is a magnet for the leaf miner fly. This fly lays its eggs on the leaves, usually the underside, and when the eggs hatch, the larvae tunnel through the inside of the leaves leaving an unsightly cavity of destruction behind them. In the past, we have slowed the leaf miner damage by inspecting our chard patch pretty regularly to remove damaged leaves, rub off all the eggs we can find, and even pinch the larvae that may already be crawling through the leaves. While this helps a little, it’s pretty depressing to see so many pristine leaves destroyed by a fly. So this season, after tolerating this problem for far too long, we made more of an effort to prevent the problem in the first place by covering the entire chard patch with a fine insect netting. I hadn’t done this in the past because our 6 foot wide roll of netting was not wide enough to cover a full bed of chard, but this year my wife sewed a custom extra wide strip of netting so we could get the job done. What a difference it made! I don’t recall discarding even one leaf from leaf miner damage for the entire season! The marketable yield from our chard bed increased by at least 50% and the time spent harvesting the crop went down thanks to the improved quality. For more photos of this crop, leaf miner damage, planting and harvest data, and links to the netting supplier we use, just check out the Rainbow Chard Crop Profile in the Classroom.
Lesson #5 - Garlic is Hardy, but it Still Has Needs
Each clove of garlic contains enough energy and moisture to begin next season's growth and establish a decent root system with minimal water. This makes garlic a very hardy crop, so much so that I wouldn't even worry about growing garlic with rainfall alone and a good layer of mulch. We have done it. The mistake I made, however, was to let this quality of hardiness make me think that garlic didn’t still have needs. Garlic can survive in rough conditions, but it can’t thrive. We have observed extreme variance in the size of our garlic heads over several seasons (as shown in the second video) and I can now say from experience that bulb size is closely linked to moisture availability. In 2017, we tried to grow our garlic without irrigation and it was by far the worst crop we have ever grown. The stems were thin, the plants were shorter, and the bulbs were small. At the time, I guessed this could have been related to moisture, but I wasn’t sure. This year, we made a point of giving our garlic patch a regular soak. We laid a line of drip tape between every 2 rows of garlic to make it easy to add water when it was needed, and it's needed regularly! In fact, this link we have observed between irrigation and garlic yield has also been confirmed by research. One study showed an increase of 50% in the fresh weight of garlic bulbs when irrigated 15 times instead of just 6 times (Silabut, 2013). I am pleased to say that the results this season confirmed our hypothesis about the importance of regular irrigation as we were rewarded with many fat juicy garlic heads at harvest time. . To read more about the 5 other factors that contribute to success in our garlic patch, check out the How to Plant Hardneck Garlic post in our Classroom.
Lesson #4 - Why Cut Once When You Can Cut Twice
Cabbage plants are typically grown until their head swells enough for a first harvest. Then the whole plants are removed to reseed another crop. There might be a better way though. Other brassicas like kale and broccoli can be cut multiple times. Why not cabbage? I heard about the possibility of multi cut cabbage in my winter research last year, but the claims were hard to believe and I couldn’t find any specific harvest records. There was no choice but to take a chance and experiment with this one myself. . This experiment turned out to be one of the delights of this growing season. I devoted an extra bed for a potentially prolonged cabbage harvest and this test cabbage patch just wouldn’t quit producing! After harvesting an initial 25kg of full sized cabbage heads, the bed continued to yield 42kg more in mini cabbage heads. That’s 67kg or 148lbs of cabbage harvested from one 50 square foot bed! . To read more about this experiment and see more specific details about the planting and harvesting records check out this post in the Classroom: Results From Our Multi-Cut Cabbage Experiment.
Lesson #3 - The Final Key to Preserving the Carrot Harvest
If you have been following us for a while, you will know that I’m a big fan of carrots, so of course I am interested in preserving the crop for as long as possible. Since our winter is pretty cold and long up here in zone 3, we need to be sure to dig out our carrots before the ground freezes solid, which is usually by the end of October. That means if we want a year round carrot supply, we need to be able to store our carrots for about 8 months from October to June. . It turns out that this is possible, but it took some tinkering to figure out the best method. The trick is constructing a home for the carrots that has high humidity but also breathability. If you let the carrots dry out, they loose their crunch and become soft and rubbery. Nobody wants that. If you you seal in all the moisture, they will rot pretty quickly. The carrots are going to sweat out some of their moisture over time and there must be a way for this moisture to escape. I’ll spare you the details of all of the things we tried that didn’t quite work and skip ahead to what appears to be the perfect storage combination that we have finally started using this year. It is a standard rubbermaid container with a few small holes drilled in the side walls, a sheet of burlap laid over the top of the carrots, and the normal plastic lid on top. This combination of elements will give your carrots the home they need to stay crisp for many months. To see the other steps we follow to store our carrot crop for many months check out this Preserving the Carrot Harvest post in our Classroom.
Lesson #2 - Biological Insect Control Works!
This was probably our highlight of the month back in August. Aphids had thoroughly infested our high tunnel, and the various homemade aphid sprays were failing miserably, so we decided to hire a crew of ladybugs to do the work for us. What a transformation it was! Two weeks after their release, the ladybugs and their larvae had nearly eradicated the once might aphid population. Flip through the photos to see the difference they made and some close up images of the larvae. For a much more detailed account of this experiment, follow this link to our Classroom post: Controlling Aphids With Ladybugs. There you’ll find videos and instructions for the release and more photos.
Lesson #1 - If You Build It, They
We took a leap of faith this spring by building a high tunnel of our own because of what it could potentially offer us in increased yields and crop protection. It’s hard to find specific data on supposed yield increases that are possible from adding a structure like this, but what I had been able to find made it seem like a high tunnel should have a positive impact on yields, especially if we chose to use it for the right heat loving plants. In addition to creating a warmer growing environment, the tunnel would also offer some insurance against hail events which have set us back in the previous two years. These were the two biggest motivating factors that set the project into motion. The added bonus for me was that I just like to build stuff like this! I am pleased to report now that the tunnel crops did exceptionally well thanks to their extra cozy growing conditions. We also saw some yield increases better than what we could have hoped for. Our cucumber beds produced 4.2 lbs per square foot and our bell pepper beds produced 2.4 lbs per square foot, both more than double the yield of the same crop varieties in field conditions! The Cauralina greenhouse tomato we selected for the tunnel yielded 4.8 lbs per square foot, and we haven’t grown that variety in the field so I can’t report whether that would be a significant improvement or not. However, we did have some field tomatoes perform in this range or higher, so I was hoping for a bigger output from our tomato beds. Lower than expected yields could be due to some shading from the cucumbers, but we’ll have to wait for next season to run some more trials. The question that remains is whether or not the increased crop performance justifies the cost of the tunnel. In the coming months, I will be documenting more about the construction process and costs to share with you all in the online Classroom so stay tuned for more details. Until then, you are welcome to ask questions below and I will answer what I can.