ZUCCHINI
OUTDOORS & IN THE GREENHOUSE
Zucchini grows great here! I’ve been growing zucchini both outdoors in the summer and in the greenhouse year-round since the garden began. Although one plant would normally be enough just for the two of us, I like the color combination of yellow and green zucchini together for many dishes. I especially like it grilled with red & orange sweet peppers and onions, but that’s another story for the recipe file. Although I am learning to save seeds and thus trying to avoid hybrid varieties, I cannot find open-pollinated yellow zucchini. I’ll continue to buy those seeds as needed, I like them so much.
There is some confusion at times between “summer squash” and “zucchini”. These are close cousins, but there is some difference. Although they’re growing conditions are identical, ZUCCHINI is generally more firm than the summer squashes, and at a small size, the seeds are smaller & less distinguishable. I prefer zucchini and rarely grow the other summer squashes.
GROWING ZUCCHINI OUTDOORS
Outdoors I typically plant one each, green & yellow in one bed along with some spinach, basil, lettuce or celery at the ends of the beds or in the middle. The lettuce & spinach are harvested early, so by the time the zucchini plants get big the lettuces & spinach are gone. Celery planted in the center, between two zucchini plants has worked well and seems to be a good combination. I look for zucchini varieties that indicate “compact” plants, which helps contain them in the raised beds both outside & in.
HAND POLLINATION
Both outside and inside I pollinate the zucchini by hand. We just don’t get enough bees or other bugs here to do that for me. I keep some duck feathers handy by the plants, swab the male stamen then the female stigma with them when those flowers are wide open. I check the plants every morning to see if flowers are ready to pollinate. The biggest problem I’ve had with zucchini is that frequently I have either all males or all females, and can’t pollinate. I’ve tried to find information about how to keep both sexes growing, but I just can’t find anything. Some sources indicate that often the plants will produce lots of males first, prior to the females, but in my experience I’ve often had lots of females and not enough males. Go figure. At times I have grown an extra zucchini in the greenhouse in early spring, and use the male flowers from it to pollinate the first females on all the squash plants (indoors & out). When I’ve gotten a good head start, I remove that plant to make room for something else.
HIGH ELEVATION GROWING TIPS: ZUCCHINI
- Grow zucchini outdoors in the summer after starting them indoors 4 weeks prior to transplant.
- Transplant them out just after your last frost, and keep them covered with frost cloth or plastic over hoops until you’re sure it won’t frost.
- Watch your zucchini and hand pollinate your them whenever you have both male & female flowers.
- Check them daily and harvest them regularly before the grow too large.s
ZUCCHINI IN THE GREENHOUSE
In the greenhouse, I typically plant just one zucchini at a time, since they do take up space, most often a yellow variety, just because I like the pretty color. Zucchini is always planted someplace where I can string it up to the beam or ceiling, to grow the zucchini vertically.
I often experience quite a bit of powdery mildew (PM) on the zucchini in the greenhouse. I spray the leaves with some potassium bicarbonate, dish soap, oil & milk. If I begin this procedure early after discovery, I can keep the PM at bay for a while, but eventually I give up and remove the plant. I keep it out of the compost pile just in case the PM will live on and spread to other plants through the soil.
The greenhouse zucchini is typically NOT bothered by the aphids I have such a struggle with in the greenhouse.
FAVORITE ZUCCHINI RECIPES
ZUCCHINI ON PIZZA Here’s a photo of a pizza I made with some zucchini, chicken & other garden veggies.
GRILLED ZUCCHINI WITH PEPPERS & ONIONS No recipe, I just marinate these with a bit of Italian dressing and grill them in a holey veggie grill pan.
CHOCOLATE-COCONUT-CHOCOLATE CHIP-ZUCCHINI BREAD For loaves I reduce the baking soda to 1/2 teaspoon at my elevation. I also really like this in a 9×13 pan–they’re more like brownies! For the brownies I leave out the baking soda.
FRENCH ONION ZUCCHINI BAKE If you like onions & zucchini you’ll like this. No changes for altitude. I sprinkle some canned French fried onions on top for a special treat.
ZUCCHINI VARIETIES GROWN
Cash Machine F1| 45 Days | A more compact plant (perfect for my raised beds) with an abundant harvest! DTH: 35 days from transplant outdoors to harvest.
Golden Star F1 | 55 Days | DTH: 37 days from transplant outdoors to harvest. Nice, firm yellow zucchini.
Black Beauty OP | 55 Days
Costata OP | 60 Days | Did quite well outdoors.
Golden Zucchini | 53 Days | Did very well both outdoors and in the greenhouse.
Nero di Milano | 45 Days | Did not do as well as the Costata.
Cocozelle OP | 53 Days | Not as abundant as the Costata, but did okay outdoors.
- Laurie
- Revised January 2024