This year Krista had the brilliant idea to divide and conquer seed/variety selection. This allowed each of us to focus on the crops that we may have more expertise in or enjoy growing more than others. Or we allow the other person to select the varieties for a crop that we like a lot in an effort to not end up with 18 varieties (like the 2015 tomato production or Krista’s cucumber selections). When looking through 5 or 6 catalogs to compare varieties, prices, etc, any simplification is appreciated.
I felt really good like I was getting this task accomplished after quickly selecting broccoli, cauliflower and carrot varieties with little difficulty. Cucumbers also should have been simple: early variety, slicing variety, pickling variety. But, I came across a variety in the Rare Seed catalog from Baker Creek Heirloom Seeds that sent me on a tangent. There were a few terms in the description that I didn’t recognize and didn’t require a pollinator to set fruit. Well, this sounded like great news so I started doing some research.
Quick biology lesson. Plants have male and female flowers (of course there are exceptions). The male flowers produce pollen, die, shrivel and fall off of the plant. The female flowers receive the pollen and then produce fruit which contains the seeds (plant babies).
Most cucumbers naturally have female and male flowers (monoecious) on each plant. This way the plant can pollinate itself. Usually the first flowers are male followed by any combination of male and female flowers. The crazy thing is that it is usually the same flower pattern of male and female flowers on each vine of the plant. However, most plants tend to be heavily male. It can be as much as 70% male flowers to 30% female flower. This drastically reduces yields as there are few flowers left on the plant to produce cucumbers.
Another crazy thing… the sex of cucumbers is inherited but environmental factors can have an effect on how that is expressed. What does this mean? For cucumbers this means that higher temperatures and longer days can increase the chance of more male flowers while lower temps and shorter days favor more female flowers. This occurrence is due to changing hormone levels within the plant.
Over the years plant breeders have developed varieties that are primarily female flowers (seriously, one male flower can pollinate A LOT of flowers). But you also need a good crew of pollinators to move the pollen from flower to flower. Bees are the primary pollinator for cucumbers. So their absence is often to blame when issues arise. Inadequate pollen can result in under developed and misshapen cucumbers. Or no cucumbers at all.
Parthenocarpic is the term that started my research. Parthenocarpic cucumbers can produce fruit without any pollination. How does that work? Turns out it’s a genetic disorder that is pretty favorable for at least one reasons we would all probably agree on. Seedless fruit: including oranges, grapes and cucumbers. (There are other reasons for seedless fruit but that can wait for another day). So great news, we can all just plant parthenocarpic cucumbers and we bypass all of the issues previously discussed. Sounds good.
Unfortunately, it doesn’t work quite that easily. If parthenocarpic cucumbers get pollinated it can cause seeded cucumbers and misshapen fruit. This can also result in decreased growth and halt further flowering. So this production method is probably not the end all solution after a season of poor yielding cucumbers. It is highly specialized requiring a greenhouse or other enclosure to keep bees (and other pollinators) out. I do appreciate the effort because I love those long English cucumbers individually wrapped (most likely parthenocarpic).
*After reading all of this about parthenocarpy, I noticed that a large percentage of varieties in the seed catalogs are parthenocarpic. So, while the literature says it is specialized blah blah blah, my best advice is to try a couple plants. You never know how things will grow in your area unless you try. Plus, if you aren’t growing for market, who cares if the cucumbers grow crooked.
So how do we choose and grow cucumbers? For many people who have never had issues growing cucumbers all of this might seem irrelevant, but one bad year (especially for market growers) and we need to figure out what’s going on. We know that it is a favorite in our shares the whole season. What is our answer to growing a successful crop of cucumbers?
So, now I know a lot more about cucumbers. This information will get added to the current list of criteria that I use to make selections. I look for early, commonly known, pickling, slicing, yield, cold tolerant (it’s always a plus if you find varieties that were bred for northern/short season climates), growth habit, disease resistant (luckily we don’t have to worry too much about disease with Idaho’s dry climate), drought/stress tolerant, and most importantly something new and fun. This may seem overwhelming but remember there is no “one size fits all”. That’s why I ended up with the following 5 varieties for 2016:
More science stuff…
Monoecious: female and male flowers on the same plant
Gynoecious: only female flowers on the plant
Parthenocarpic: genetic mutation in which female flowers produce fruit without pollination
Cucumbers are in the same plant family as watermelons (Cucerbitacea), so much of the information can also be applied to growing watermelons.
Most of this information came from World Vegetables (a college text book that is frequently referenced at my house).
Also check out http://masteringhorticulture.blogspot.com/.