AUGUST 9th, 2014
Last week at Farmer’s Market a lady in a Hawaiian shirt with a matching visor came up and began asking me questions about her zucchini plants. It was obvious she knew more about them than I did—She knew they had a male and a female flower. She knew that if they were not producing fruit, she may need to hand pollinate them. But what she didn’t know was why with all this knowledge she still did not have zucchini on her zucchini plants.
All I could respond was that I wished The Farmer was here—at Farmer’s Market. He is just the smartest man about plants that I know! And then the surge of new veggie lovers crowded our table and the lady in the Hawaiian shirt with the matching visor and I parted without even sharing a name.
This post is for that woman with a heart-felt thank you for asking the question! I puzzled over her dilemma all week, but it wasn’t until today that I could get to the computer to look for some answers.
What follows is what I found about Male and Female blossoms on zucchini:
Unlike other common vegetables such as beans and peas, zucchini produces both male and female blossoms. Because the male blossoms appear first to attract bees, your zucchini plants may produce blooms for a week or more that do not set fruit. The male bloom contains the pollen necessary to pollinate the female blooms, but does not produce fruit on its own. Male blooms appear on a long slender stem.
Female blooms appear several days to a week or more after the male blooms. These blooms contain a swollen ovary at the base of the bloom that looks like a miniature zucchini. These blooms must be pollinated before the young fruit can grow.
My first thought is this has been an odd year—many of the vegetables have been delayed and the season seems to be a little out of kilter. If the male blossoms come first…and it says that could be a week or more before the female blossoms appear…then it could be that is the reason for no fruit yet. Not knowing when the zucchini were planted makes it hard to determine if this is the sole factor. But then, seldom is there a ‘sole’ factor.
We have CSA gardened now for three years. The first year and this year we got the garden in about the same time—the zucchini were planted between the 2nd and 3rd weeks in May. In the first year the zucchini’s first harvest was the last week in June. This year the first harvest was the second week in July—a difference of two weeks.
Zucchini are considered one of those 50 day-er’s…my term. It takes about 50 days for them to mature and for harvest to begin. The 50 day-ers are those things that are in the first share and the second and third…until the next wave of veggies come into their own. It’s like we have been singing a song and it’s been the same melody with slightly different words, but now we are going to bridge into a little higher range with a faster pace. (That’s where the garden is right now–the bridge to the next wave of veggies.)
Anyway, the Hawaiian shirt lady with visor could just be experiencing a lull before the female blossoms appear and pollination begins. But it seems so late~
As I read further, I found that if the male and female flowers are present but fruit doesn’t set it could be a lack of pollinators:
If fruit is not formed after the female flowers are present, the most common problem is lack of pollinators. The pollen is heavy and moist and has to be physically transferred from the fresh male flower to the newly opened female flower for fruit production to occur. Honeybees are a common pollinator, although native squash bees do a better job. Bees collect the pollen grains from male flowers on their legs and body hairs to feed to their larvae. Bees also visit female flowers to collect nectar as food for their young. As they crawl about, pollen gets transferred to the female stigma and the flower is pollinated. If the pollinators are missing, no fruit will set.
This reminded me of my own dilemma with our Yellow Squash. They are setting on the young fruit and then withering and rotting—a type of end blossom rot. Pollinators are very important—and just the fact that they are there is no guarantee that the job of pollination is successful. There could be lots of bees buzzing. There could be a shortage of bees to carry on pollinating. They could just be gathering the pollen grains and skipping the collection of nectar–Missing the female flowers and hitting only the males—which after all are the flowers that attracted them in the first place.
And while we are talking bees—Did you know there is a Squash Bee?
You can also try importing native squash bees into your garden by collecting wilted squash flowers from someone who does get fruit set. The male and female squash bees sleep in the newly wilted flowers and chew their way out of the flowers the next day to mate and pollinate squash flowers.
It is not always easy to assess if or how many bees are buzzing in the garden. I was convinced our problem with the Yellow Squash was a shortage of bees–read that while reading on squash when helping a member identify an odd squash that came in her seed packet and didn’t match the rest. Brandon Bryant mentioned hit and miss pollination by bees. Earlier in the summer I was crouched among the prickly squash leaves one morning and did not see one honeybee—Odd, I thought. Then I recalled Rachel Carson’s book Silent Spring about the unintentional loss of critters after the use of DDT and other pesticides and thought we were entering the dark days of doom. I shook myself out of that quickly though when I realized the zucchini were right next to the Yellow Squash and there was definitely no pollination problem there! Abundant pumpkins were three rows away, and watermelons four rows the opposite direction.
The last point on the lack of female blossoms or fruit is temperature and moisture:
Zucchini grow best in daytime temperatures above 75 degrees Fahrenheit. If the temperatures are too cold or too hot, pollination does not occur. Bee activity also slows in hot weather. Wait until temperatures are warm and steady to assess whether fruit production is occurring. If fruit doesn’t form under good temperature conditions, flowers are not getting pollinated. Lack of moisture or fertilizers can also affect pollen production, fertility of female flowers and subsequent fruit development.
I know not whether any of this information will help my friend in the Hawaiian shirt with the visor but it hit the nail on the head with the Yellow Squash. It is in crap ground that does not hold moisture and I’m sure is lacking fertility. When the weather was HOT, the poor squash were wilted. The Farmer gave them a good long drink, and then they were fine…but only for a few days. If the plants wilt often the ground probably lacks the soil profile to hold moisture once it is there—and to hold the nutrients that are found in the moisture or activated by the interaction between the plant and its soil.
The Yellow Squash are still struggling, but they have improved with some foliar feeding of magnesium and an organic supplement. We are looking to load that bottom ground with something this fall that we can till-in in the spring to start improving the quality of the ground—building it up. When there are fertility issues in the soil, they affect the fertility of the plant and the production of healthy fruit. Healthy soil builds healthy plants. Healthy plants build healthy food. Healthy food grows healthy people and healthy communities.
Hope there is something in this post that can help–Timing, weather, fertility, moisture–there is seldom a sole factor. But don’t give up or lose heart. Plants need those blooms for their fruit…they want to produce–that’s their goal in life. We want them to produce fruit…the main reason we harvest and pick is to keep them producing that fruit…but not the seed. Zucchini is one of the most prolific–I think it will come along. Watch, think, and wait.
Thanks for the question Lady in the Hawaiian shirt. Hope to know your name sometime–
The Farmer’s Wife
Posted by Bonnie on August 10, 2014 at 2:24 pm
Terri, you amaze me. With all you have to do, you still remember the question and think about the answer! And, then find the time to research it………now we know a lot more about squash.
Every year is different……the barley was a month late going in this year but the harvest was right on time and it is a wonderful crop. The other field crops were about average in the time they were planted and look about average in yield…..maturity on the corn may be a bit later but I think it will mature before frost. Does not matter to us but it does to lots of others.
I read everything you post. Thanks for including me. Bonnie
Posted by Barb Love on August 10, 2014 at 12:58 pm
Great info….my stuff is ALL late, and I am sweating the zucchini! Best thing, though, is your emphasis on good soil and observation…garden on! Barb Love