Growing Squash
- Squash have separate male and female flowers (monoecious).
- Flowers are edible
- Companion plantings include corn, lettuce, onions and radishes
- Avoid planting with potatoes, tomatoes and eggplants
- Many varieties have tendrils that help the plant climb and hold fruit off ground
- Squash can be grown in containers (5 gallon minimum for 2 plants – same variety)
- Squash vines can be grown onto trellis or support
- Squash plants need space (Either horizontal or vertical)
- Squash are heavy feeders fertilize monthly
- Do not let soil dry out
- Squash need POLLINATORS to produce fruit
- Harvesting most squash early is not a problem
- Harvest when stems harden and fruit are no longer increasing in size
- Plant different varieties of squash at least 20 feet apart to avoid cross pollination
- If unable to distance separate different varieties, strongly consider hand pollination
- Early season, cool temperatures or irregular watering favors male flower development over female flowers
- Few pollinators are found early in the season – consider hand pollination
Planting Squash Seeds
- Squash do best in fertile, sandy soils pH 6.0 - 7.0
- Squash are very cold sensitive and seeds may not germinate with soil temperatures below 60°F
- Consider hill planting to increase soil temperatures
- Consider using ground covers or other strategies to increase soil temperatures
- Place seed 1 inch deep. Place seed in soil on its edge – not flat
- Germination 8-12 days typically – dependent on soil temperature
Transplanting Squash
- Harden off plants before placing in garden.
- Squash are root sensitive to transplanting – be careful in handling plants.
- Consider burying portions of vines to encourage secondary rooting.
- Squash are heavy feeders apply manure/compost or fertilizers monthly.
- Do not let soil dry out! Try to keep the leaves dry.
Squash Pollination
- Squash can be hand-pollinated:
- Use an artist’s paint brush, small fine comb, or tooth brush. Wipe across several male anthers, then across the female stigma. Best to do this early morning. Flowers close in early afternoon.
- Clip off male flower. Remove petals. Then swipe anthers across the female stigma. Best to do this early morning. Flowers close in early afternoon.
- Or wait for help
- Bumble bees, beetles, bugs and butterflies can pollinate squash plants.
- Squash bees in particular are important.
Squash Pests
- Squash vine borer
- Squash bug
- Cucumber beetle
- Squash beetle
- Aphids
Squash Diseases
- Downy Mildew & Powdery Mildew
- Mildews can be traced to watering procedures and air flow around leaves
- Blossom End Rot
- Blossom end rot is related to soil calcium deficiency (rare). Similar appearance is from flower not being pollinated
Information provided by Dave Long, Lake Tahoe Master Gardener Summer 2024