Everything you need to know to grow squash

Zucchini bush in center

Monday, May 20, 2024

Bush type zucchini squash

Squash is amazing.  It spans from huge pumpkins to small petit pan squash.  From the summer kings like zucchini to the fall princes like pumpkins.  They have an amazing array of sizes, shapes, and tastes.

Squash originated in Mexico.  There are cave drawings from 8000 to 6500 BC depicting squash and the oldest remains found are from 8750 BC.  Squash was grown extensively by Native Americans as part of the “Three Sisters”-squash, corn and beans.  These three support each other's growth.  Beans provide nitrogen to the corn and squash.  The corn provides the stalks for the beans to grow up on.  

The sprawling squash vines crowd out any weeds.  

Squash love organic matter.  If you throw a few seeds in your compost pile, you will be rewarded with exuberant vines.

Zucchini is a favorite summer squash and full of nutrition.  It contains antioxidants, carotenes, lutein, folates, potassium, vitamin A, vitamin C, and B vitamins.  For more specific nutritional information, Summer squash nutrition info

Plant squash when nighttime temps are 55F or warmer consistently.  Add a fertilizer rich in phosphorous a week after transplanting, when flowers first appear and again when fruits begin to form.  They love water, too.  If growing in a pot, keep well watered and don’t let dry out.

Don’t panic when the first blooms fall off without producing any fruits.  There are male and female flowers.  If yours falls off, it was likely a poor guy that withered without the love a gal.  There can also be some false starts with malformed fruits.  Don’t worry, the plant will put on more blooms and you will be on your way to zucchini overload before you know it!

Baby acorn squash, blooms still attached

There are two basic categories of squash-winter and summer.  

Winter squash are those that take until late fall to ripen and can be stored inside for months.  Butternut squash will last until June in my pantry.  Winter squash includes butternut squash, acorn squash, spaghetti squash, Hubbards, turbans and pumpkins.  Each vine does not produce many fruits. It is typical to get 2-3 winter squash off a single vine.

Winter squash you typically leave on the vine until the vine dies and the fruit loses its sheen in the fall.   Then bring inside and store in a cool, not cold, dark place.

Turban squash

There are some amazingly diverse and cool winter squashes/pumpkins, from the bumpy and blue hubbards, to traditional pear shaped butternut to the exotic "turban" squash, so named because of the hat it appears to be wearing............  

From left to right-Hubbard and Butternut squash

Baby zucchini squash, blooms still attached

Summer squash can be harvested all summer long.  I have grown them successfully in a pot or garden bed.  This year I am planting in the flower bed and my potato boxes.  Summer squash include the ever popular zucchini, cushaw, pattypan, and yellow crookneck.

If growing summer squash in a pot, look for the bush varieties.  These are much more manageable.  I would recommend putting in a pot with a water reservoir as well as zucchini's love moisture.  Decorative container gardening for edibles

Zucchini is notorious for getting huge overnight.  It is important to pick summer squash when smaller.  As they grow large, they become very seedy and just don’t taste nearly as good!  Check them daily.  If left to grow too large, you can always use them for zucchini bread which is delicious.

Since I have switched to Trombetta squash.  It is a sprawler so I grow in the garden bed or our large potato boxes.  I prefer it because it seems impervious to disease and pests, produces less at one time and over a longer period, and you can harvest the fruits young for use as a summer squash or if you wait too long, you can harvest and keep as winter squash.  I still have several in the basement cellar from last year.

Since summer squash produces so many fruits, it needs to be fertilized and watered regularly in dry conditions.  I fertilize with an organic, granular fertilizer at least once a month.  I'll use tomato fertilizer on all my fruiting vegetables when I fertilize my tomatoes as it is good for all fruiting vegetables as well.  You can also make your own.  Make your own all natural, complete fertilizer

The two biggest pest problems are squash bugs (left) and squash vine borer (below left are eggs and right is the adult).  Inspect the plant for squash bugs.  You can wear gloves, pick them off and throw them in a bowl of soapy water.

Natural, organic pest strategies and how to make your own bug sprays

The squash vine borer is best thwarted by planting early or late.  They fly in mid-June.  If planting early, be sure to inspect regularly the stems for any eggs.  Scrap off any that you find.  When the eggs hatch, the catepillar will dig into the vine and eat its way through its length.  You will have a strong plant one day and a wilted on the next.  You can wrap the stem base as a preventative.  The good news is that your plant does get infested, you can replace with another one.  They grow quickly in warm temperatures and soils of summer.

The cucumber beetle can infect the plant with a bacterial disease called wilt or cucumber mosaic virus.  The cucumber beetles we get here look like yellow/green lady bugs (left).  There are also striped varieties (below).

Again, the gloves, pick and throw in soapy water technique works.  Or if you are not squeamish, you can just squish them.

In late summer in areas with high humidity, you can get powdery mildew.  This can be treated by spraying with baking soda, copper, fresh whey and other organic fungal sprays and soil drenches.  When watering be sure to not get the foliage wet and water in the morning so any extra is quickly evaporated.  I have found that planting a second plant around the first of July is the best approach.  This plant will be kicking in as the second starts slowing down.  Summer garden tips

With zucchini, you are begging people to take them come mid-summer.  I found some great ways to use all that extra  What to do with all that zucchini?!   I make into spaghetti noodles, use as a substitute for lasagna noodles, stuff, dry, and freeze.  You can also pickle or high pressure can.  There are many ways to creatively use and to preserve your zucchini harvest!  

If you bought a heirloom or open pollinated variety, you can easily save the seed to grow next year's plants.  From your best plant with no disease, let one get large, remove from the vine and leave it out in the garden bed.  The inner flesh will deteriorate leaving the seeds.  Just scoop out the seeds, put in a plastic baggie, date and keep in the frig for next year.  You can also scoop out the seeds from the fruit right off the vine and leave the seeds indoors to dry on a paper towel or plate.  Seed saving-fun, easy and a cost saver

If there is a variety that you love the looks and/or taste of from the store or farmers market, save the seeds and grow some of your own next year!  If it is an heirloom, it will come back "true" to the parent.  If it is a hybrid, it may be a surprise squash.  Either way, it is fun to try.

What do the terms GMO, natural, heirloom, organic, hybrid really mean?

Summer squash is a fun one to grow because it is so productive and easy to grow.  Just a few seeds will provide so much food!  My go-to squash is Trombetta (also called Rampicante or Tromboncino).    You can use just like zucchini or if left on the vine, you can harvest and store like winter squash.  It doesn't pump out as many fruits as once as zucchini so you don't have to worry about having more than you can eat.  It produces all the way to frost.  So far, I have had minimal squash bug or powdery mildew with this variety.