Last year we grew a wide range of different varieties of onions
in the large bed of the Simple Garden. It was great to be able to explore a much
bigger range of different types of onions that is possible with seeds, as previously I always
relied on planting onion sets, of which there are only a few different varieties available.
I was pleasantly surprised how well most of the varieties grew, but some of them definitely
produced a lot more that others, however, yield is not the only factor to consider
when selecting varieties to grow in the future. Storability is important of course, as onions that
can last longer in storage tend to be more useful, at least for part of the year, and the different
flavours and potential uses in the kitchen should also be part of the selection process.
Measuring yield is relatively easy, and I set aside a few onions from each variety to see how
long they would last in storage. But to evaluate the flavour,
I decide to give a selection of each of the 15 different onion varieties to a few friends,
hoping to get some useful feedback, and I ended up learning more than I expected to.
We have conducted several vegetable variety trials over the past few years, with the goal of finding
varieties that thrive in our local conditions, and to explore the diversity of options available.
In Ireland, the lack of onion diversity in the stores is reflected in the limited range
of onion sets for purchase, consisting mainly of typical yellow-skinned storage
onions with few red options. So, I wanted to include a few
unconventional options in the trial, as well as a selection of more typical types of onions.
Trials like this have limitations of course, as not all of the onions are best sown at the same
time, or even grown in the same way. This trial was also impacted by my
lack of experience growing onions from seeds, germination issues from some of the older seed,
and the seedlings were a bit stressed before transplanting.
But I was pleasantly surprised with how well most of the 15 different varieties grew,
with very few issues of bolting or rotting in the garden bed, and an overall yield of over 9 kg/m2.
This was significantly better than in previous years when we grew a similar crop from onion sets,
which convinced me that growing from seeds was probably a better option,
especially considering the diversity of onions that grew well in this first trial.
Based on the yield and appearance of each variety from this one trial, and before taking storability
or taste into consideration, I decided to pick three of them that produced quite well,
to grow in the other gardens this season, including a hybrid standard type of onion,
a really large variety, and one with interesting rose colouring inside.
If I wanted to expand that list I would also include an open pollinated standard type of onion,
an elongated one and a red variety, all of which would give a fairly good range of
different types of onions, and I would have been content to not grow the others again.
But after getting some interesting feedback about the taste and cooking quality of these onions,
and seeing how long all of them stored, I would change that selection a bit.
When it comes to growing onions, it is important to harvest them at the right time and to cure and
store them appropriately, so that they remain firm and usable for as long as possible.
And selecting a variety that can store well, increases the chance of enough
of the onion crop from the previous year lasting until the new onions are
ready from the gardens the following season. To test the storability of the onions we grew,
I selected 3 onions of each variety, and hung them in our cool and dry pantry.
I basically sacrificed these onions for an experiment,
and I avoiding eating any of them, basically waiting until they started to rot, or sprout.
Out of all these onions, only two rotted in storage, so far, which is less than in previous
years and perhaps that is a benefit of growing from seed, rather than from using onion sets.
But with such a small sample size, I don’t know if
this is just a random occurrence or an issue with these particular varieties.
Two of the longer varieties sprouted much earlier than the others, which was expected as these
varieties are not meant to be storage onions, but still managed to last until the winter.
By March, one or two of the onions of five more varieties had started to sprout,
but the rest remained in good shape. And by the end of April, only 3 of
the varieties still had firm onions that had not started to sprout yet, the remaining onions from
the two varieties that had rotten earlier in the winter were still in good condition, and another
three varieties had only just started to sprout. So these 8 varieties all have decent storage
ability, with some possibly better than others, and the other 7 varieties did not
store well, at least in this one trial. I had also kept three huge onions from
one variety that had grown separately in a grow bag, and these sprouted significantly
earlier than the smaller onions from the same variety that were growing in the soil.
So the growing conditions, the time of harvest or the size that the onions grow to,
can all potentially influence how long onions can keep, so it is not just about the variety.
I now realise that I use to place too much emphasis on the storability of onion varieties,
when in reality we only rely on onions that store really well for a few months of the year.
During the rest of the year, we can rely on fresh green onions from the
polytunnel in the spring and early summer, many other options in the summer and autumn,
and it seems that most onion varieties will last long enough to be useful for a lot of the winter.
When I only grew one variety of onion, storability was important, but by
prioritising this one attribute, we may have missed out on the possibility of higher yields,
different uses and a diversity of tastes. I gave a few onions from all 15 varieties to
four friends and asked for feedback on their taste and how they were used in the kitchen,
and the feedback I received showed me how limited my own appreciation of onions have been.
One friend, who enjoys eating raw onions, did a full taste test of all 15 varieties, and provided
feedback on how easy they were to peel and chop, how many tears they causes, their taste raw and
how strong they were, and then gave a ranking. This of course is a personal preference of one
person who enjoys eating raw onions, but it’s something that I hadn’t really considered before,
and if we are growing onions for other people, then this kind of feedback is really useful.
Another friend is a baker who produces delicious breads for our community,
and he sent amazing feedback over a few months as he used the different onions in his cooking.
This showed me how different people use different onions, and taste them in
ways that I am not familiar with. With other crops like tomatoes,
I really enjoy the different flavours, textures and juiciness of the different varieties,
and will regularly select a tomato from a particular variety based on how I plan to use it,
and I grow a quite a few different varieties of tomatoes to get this diversity of flavour.
However, I’ve never really done that with onions before,
or at least I have not been paying attention to the flavour of the onion.
This kind of feedback from someone who focuses so much on the particular flavours of the bread
he makes, together with the feedback from the other people who had a chance to sample
the full set of onions, has made me realise that I am definitely missing out on a lot.
So now that I have observations about how the different varieties grew, reasonable yield data,
a better sense of what onions will store well, and some great feedback about taste,
I can make informed decisions on which varieties would be useful to grow again.
It would be tempting to go with the standard yellow skinned hybrid variety that seemed to
store the longest, but the other hybrid onion also lasted quite a long time,
produced a lot more in this trial, and got great feedback from the taste testing.
So this seems like it might be the best all round onion to grow again, even if the seeds are
more expensive and can’t be saved, and I am glad that this is one of the varieties that I already
selected to grow this year in the other gardens. The really big variety that we also grew again
this year, lasted longer in storage than I thought it would, and with the huge yields
and great feedback as a salad onion, it still seems like an excellent choice.
The third variety that I already selected to grow this year,
also got great feedback from the tasting trial, and stored reasonably well, so I am happy to keep
growing this attractive open pollinated variety. Another productive general purpose variety that
I thought would make the cut, didn’t store very well, and didn’t rate very highly in the taste
test, which is a shame as I am saving seeds from this open pollinated variety this year.
I had dismissed another really productive variety because a few of the bulbs spit open at the base,
and it didn’t store very well, but it got excellent feedback from the taste test.
I wonder if some of the issues with this variety were because the germination was so poor from
the old seed that there were very few plants in that section, and they all got too big,
causing them to split open and not last as long as they could, so I might need to rethink this one.
Of the three red onions that we grew, the variety that produced the biggest yield also
seemed to last the longest in storage, and got fairly good feedback about its flavour,
so this variety seems like one to choose for a red onion.
I would like to select one of the two elongated varieties, but had mixed feedback about their
taste and possible use, and I think we were eating them at the wrong time of the year,
so I think I need to wait until I have more experience with this very different type of onion.
Based on this one trial, I could easily select a few varieties of onions to grow in the future,
as they will likely be good enough. But there are still questions about few
of the varieties, and different weather conditions each season could lead to
significantly different results, especially if there is a lot of downy mildew around,
as I don’t know how resistant any of these varieties would be to that problematic infection.
So I thought it was worth doing another variety trial,
especially as some of the older seeds in my collection may not be viable for much longer.
We planted the full set of 15 onion varieties in the smaller polytunnel as an overwintering crop,
and to see how all they would do in these very different growing conditions.
The plants have already grown quite large, and we plan to harvest a lot
of them to try as fresh onions rather than waiting for them to dry and cure.
We have also repeated the trial in the Simple Garden this year,
with all 15 varieties sown earlier this spring, and we have made sure that there is similar
densities for all of the plants, which I think was an issue with a few varieties last year.
In the other 4 family scale gardens, we are growing 3 different varieties,
and while I am still fairly content with this selection,
there is no significant reason why I would not grow even more varieties.
I use to grow onions as a basic storage crop, with only a few onions harvested fresh in the
early summer, and I think I need to expand my approach to growing onions.
Although the range of onion varieties available may not be as extensive as it
is for crops like tomatoes, I have learned from the trail last year that there is
still a wonderful diversity of onions available. Particularly if we expand our use of the onions
in the kitchen, and for me this would involve paying closer attention to the
qualities of different onions, and to learn how to appreciate the flavour of raw onions again.