Hand Pollinating Squash

Even with the many other websites that overview hand pollinating squash, I figure that it cannot hurt to review the process. Just like melons, squash are monoecious: meaning that they have separate male and female flowers that grow from the same vine. In order for fruit to mature, this type of plant requires a pollinator to remove pollen from the anther of the male flower and deposit it on the stigma of the female flower.

Immature Male Squash Blossom

Female flowers are identified by the bulbous protrusion on the stem right below the flower, whereas male flowers consist of a thin stalk leading up to the flower.

Depending upon the type of squash you are growing, female flowers may take a while to appear. The 90 days that I waited for my Long of Naples to produce female flowers was nearly enough to persuade me to cut the whole plant down.

Immature female Squash Blossom

Other reasons why female flowers may not grow include a lack of some nutrient. On one occasion, when I had a large zucchini plant with no female flowers, the plant quickly began to produce flowers after an application of a little bone meal. However, the correlation could be considered questionable. Whether the production of female flowers was because of the bone meal or whether the plant would have produced female flowers anyway was difficult to determine.

Mature Female Squash Blossom (side view)




Mature Female Squash Blossom (front view)

Pollinating of squash can occur as soon as a female squash blossom has been identified and that blossom begins to open its large flower. To pollinate, I identify a blossoming male flower, pull it by its stem, remove its large petals and rub the pollen from the male anther gently around stigma of the female flower. As there are usually more male flowers than female flowers, I usually use repeat the process several times using multiple male flowers.



Mature male squash blossom (Tucson ants will even eat pollen!)

Pollinating the female stigma with the male anther

So – how do you know when you’ve pollinated your squash correctly? Within a week the squash should either begin to grow or shrivel up. If it grows, then all the conditions were right for pollination and fruit set.

Squash set fruit - this is usually a good thing

If the fruit does not set and shrivels, this may not be the gardener’s fault. If I have multiple fruits setting at the same time on the same vine, the vine will often abort the less developed fruit in favor of a heartier fruit. This does not mean that I am a bad gardener, but rather – if I pollinated all the fruit correctly then I see this as the process by which the squash plant is determining its next generation of offspring. A stressed plant in a poor environment may favor the smaller fruit over the larger fruit, to enable it to perpetuate its seed; whereas a vigorous plant in a healthy environment will favor setting larger fruit with vigorous seed. 

Withered squash fruit - this could be a bad thing

When growing squash, it is wise to pick a variety that you can sustain in your garden and your climate. In 2010 I grew Athena (hybrid) cantaloupe in my garden. The vines set so much fruit (at the same time the plant was under intense environmental duress) that the plant literally killed itself. Slow and steady wins the prize: It is better to choose a variety that works in my environment then to pick a variety that produces so abundantly that it kills itself before the fruit matures.

Early Summer Harvest

Lately I have been gathering veggies out of my garden. Here are a few of my tomatoes, some Royal Burgundy bush beans and a Carosello Massafra cucumber. The whole family enjoyed these for lunch. Yum!

I love summer time in my garden!

Starting Sweet Potatoes in the Garden

A few years ago when I began working with sweet potatoes, I preferred to grow out the slips from sweet potatoes cut halfway in a jar. However, as I have experimented with different techniques I have found that starting sweet potatoes in sand or soil is much faster, howbeit a bit more complicated.

Putting Sweet potatoes out for transplants

 

Placing the sweet potatoes in the Garden

 

 

Purple Sweet Potatoes for Slips

 

So – what makes starting sweet potato slips in the garden tricky? Disease, nematodes, and various other factors have led to farmers to grow out small plants (or slips) from sweet potatoes rather than planting the tubers themselves. Transplanting sweet potato slips can be a rather simple process in a very moderate climate (where sweet potatoes do not grow well). In contrast, in hot southern climates (where sweet potatoes grow very well) transplanting can be much more difficult. This is because by the time the slips are ready to plant in May the 100ᵒ Fahrenheit (38ᵒ Celsius) daytime heat cooks the roots of the sweet potatoes down through the first 6 inches of soil. This means that either the roots must be very long or the plants must be given additional care until they establish themselves.

 

 

All Purple Sweet Potato Slips

My experience this last month with growing and transplanting sweet potato vines has taught me that transplanting slips requires timing, hardening off, and recovery time. By timing I mean that I have found that it helps to transplant the slips in the evening. By doing this, it gives the roots a little more time to enjoy cool soil before the sun and heat begin to stress the plant. In very hot climates sweet potato slips need to be hardened off before they are exposed to the full sun. Until the plants stop wilting, temporary shading really helps to give the roots time to grow and helps to “harden off” the plant. Even with planting at night and shading, it may still take several weeks until sweet potato slips are ready for the intense heat of the Arizona sun.

 

Sweet Potato Slips recovering

 

More recovering Sweet Potato Slips

 

One other nonconventional means of transplanting sweet potatoes is the growing of sweet potato slips from tubers in the garden, then removing the tubers from the garden. This is the opposite idea of transplanting slips. With this method I mark (with a stick or some other marker) where I want to plant a very healthy disease-free sweet potato. Then, I put the sweet potato in the ground and cover it with garden soil. I then water it, just as she would any other plant in the garden. Next, I wait until the sweet potato grows out and the plant becomes established. Once the plant is about 18” long, then you carefully poke around for the potato and (with a fingernail or another sharp object) I remove any vines from the potato. Then I pull out the original sweet potato and fill in the hole with soil. With this method, you have to be very careful to keep from disturbing the roots of the growing slips. By doing this, you can keep from losing the 2-3 weeks of shock and recovery required when transplanting the sweet potato slips.

Several weeks later - the vines have recovered

 

This “starting slips in the garden” method is fraught with all kinds of potential disease issues. However, if you have never had disease problems with sweet potatoes and are using very healthy disease-free tubers, then you might be willing to take the chance of keeping sweet potatoes in your soil just long enough to allow the slips to establish themselves.

Sweet Potatoes Started in the Garden - with tubers removed

 

The Carosello Massafra

Carosello Massafra Seedling - Late March

The round Carosello Massafrahttps://cucumbershop.com or Massafrese is one of the most beautiful cucumber-melons that I have ever grown. As its name implies, it originates in Southern Italy. One of the many reasons I love growing Carosello and other cucumber-melons is because of how quickly they produce fruit. These Massafra cucumbers were planted in late March and have been enjoying watching them grow.





Cut paper towel roll to protect against cutworms

In general, melon varieties (C. melo) that are cultivated as cucumbers do well in the heat. While my regular cucumber varieties (C. sativus) wilt during very hot times of the day, my Carosello never do.



Carosello Massafra - April 11th

Another C. Massafra on April 11th

There is a regular pattern with all the cucumber-melons that I have grown so far, so that I know about when to expect to see both the male and female flowers.



Trellising Carosello plants on Tomato Cages



Carosello Massafra - May 6th



The Carosello Massafra produces melon flowers





Carosello Massafra cucumbers

Carosello Massafra melons around May 20th



Last Saturday I picked some Massafra fruit for a taste test. One of my children recently tested positive for an allergy to cucumbers and pickles (C. sativus). Luckily he tested negative to an allergy to melons (C. melo), so he was able to help me with my Massafra taste test.

Maturing Carosello Massafra melon

So – how did they taste? My best description is super-juicy on the inside and lightly crispy-crunchy on the outside. The taste was that of any other freshly picked cucumber. In short, it was delicious.

Morning Munching of Massafra Melons - say that 10 times fast! (=

Angelo and my other Italian gardening friends at Amicidellortodue will have to forgive me for stealing their idea in some of the photographs that I took of my Carosello Massafra.

Recently, I found a really good page on making a summer salad with this variety and the Massafrese - howbeit the translation for the carosello variety "Barattiere" Google translated as "swindlers". This has to do with the nickname of that variety of carosello which, I am told, has more to do with the personality of the farmer who invented the variety than with the carosello variety itself.

The Carosello Tondo Massafra

Hand Pollinating Melons

At the beginning of each summer it often takes a while for Tucson’s wild (and domestic) bees to find the flowers in my garden. Often, during this time of year, I look around my yard wondering where the bees are hiding and conclude that if I want my vegetables pollinated then I will have to do it myself.

Male Melon Blossom - front view

Members of the Curbitaceae family (Cucumbers, Melons, and Squash) are monoecious. The Latin of this name means “one house” and refers to the separation of the reproductive parts of the plant into individual male and female flowers that grow on the same plant. The technique of hand-pollinating monoecious vegetables is pretty straight-forward. Here are some pictures to aid in hand pollinating melon vines.

Male Melon Blossom - side view

Before pollinating, it is important to ensure that both male and female flowers in bloom. Male flowers can be identified by the small short anthers with pollen in the middle of the flower and the thin stem, devoid of bulging, leading up to the flower. In contrast, female flowers exhibit a roundish folded stigma in the center of the flower and a thicker immature shape which contains the unpollinated fruit.

A Female Melon Blossom with immature fruit (Left)

Once the presence of a male and female flower have been verified, then comes the pollinating itself. With melon flowers I just pick the male flower, leaving as much stem as possible attached, and pull back the petals to expose the anthers.

Pulling back the petals of the Male Blossom to expose the anthers



Exposed Anthers of Male Blossom

To pollinate, I insert the male flower into the female flower just enough so that I can feel that the male anthers just make contact with the female stigma. One technique I found very effective to avoid damaging the female stigma is to gently rub the male anthers around in the female flower to release the pollen. After pollinating I then toss the male flower aside and hope for the best. If you desire to increase chances that pollination will occur you can either pollinate again with another male flower or you can wait until the next day to attempt the process again. This will help you to overcome male pollen that is not viable or a female flower that is not fully mature.

Pollinating Female Melon Blossom with male Anther

In general, both male and female flowers have a window of opportunity in which the bees (or people) can complete the pollination process due to the limited timespan of male pollen viability and female fruit receptivity. Male flowers lose their viability when the flower petals turn a pale color and close, while unpollinated female flowers are usually identified only after the fruit part of the stem turns yellow wilts. In order to encourage consistent flower production, I regularly remove any wilted fruit or pale flowers.

Female Melon blossoms progress (left to right): Immature, Pollinated, and Fruiting

Pollinating your plants may be necessary if you are growing in a greenhouse or if you need to isolate a specific vegetable variety (cultivar) from another cultivar that you are growing. If you are rouging or culling a specific variety for breeding purposes, it is important to pollinate your own plants by selfing. Rather than crossing plants using male and female flowers from different vines, selfing isolates qualities of a specific plant by only pollinating female flowers with male flowers of that specific plant. Once you have isolated the qualities of a vegetable variety and produced seed, you can then replant that seed to create a landrace (a large population of a variety that is adapted to your climate) by crossing as many plants of the new variety as possible. The purpose of a landrace is to keep future plants vigorous and strong by increasing genetic variability within a given population. Lack of cross pollination within a vegetable variety can weaken the variety and eventually lead to inbreeding depression.

So – why should a gardener hand-pollinate their melons if there are no natural pollinators? To watch as the female fruit grows.

A pollinated melon sets fruit and begins to grow. =)