Sacramento Digs Gardening logo
Sacramento Digs Gardening Article
Your resource for Sacramento-area gardening news, tips and events

Articles Recipe Index Keyword Index Calendar Twitter Facebook Instagram About Us Contact Us

Hot and hazy skies affect harvest

Smoky conditions get compounded by heat

sunburned tomato on vine
Sunburned tomatoes are among the unfortunate effects of the current heat wave. (Photo: Kathy Morrison)

Sacramento already has experienced its hottest day ever in August. Now, we have smoky skies, too.

What’s that doing to the zucchini and tomatoes?!

Sunday’s 112 degrees set an all-time record for August, according to the National Weather Service. That temperature may be equaled again Tuesday and Wednesday, or even surpassed. An extreme heat advisory continues through 9 p.m. Wednesday.

In addition, the revised forecast puts triple digits on every afternoon through next Tuesday, extending what already is shaping up to be a record hot streak. High temperatures have hit over 100 every day since Aug. 13. Average for mid-August: 92 degrees.

In addition, overnight temperatures have stayed very warm: 70 degrees and above. That has an effect on plants (and people), too.

Add to that record heat Sunday’s thunderstorms and lightning strikes, a rare monsoonal system weather watchers say happens once every 40 or 50 years. The storm system produced precious little rain in the Valley (0.02 inches), but started dozens of wildfires.

Smoke from those fires reduced air quality to “unhealthy” over much of the Sacramento area Tuesday. With no Delta breeze, expect those hazy skies to hang around.

Both heat and smoke will have notable effects on two of our favorite late summer crops: Squash and tomatoes.

In this weather, zucchini develop little baby squash that start out OK, but never seem to develop. It rots before it reaches 4 or 5 inches long.

The Brits call it “courgette rot,” referring to the English name for zucchini. It’s due to insufficient pollination.

While skies are smoky, bees return to the safety of their hives. They’re not out, working the squash blossoms, as they normally would do on a summer’s day.

Extreme heat further complicates bees’ lives. If temperatures top 100 degrees (as it has almost daily this month), worker bees need to bring water back to their hives, from one quart to a gallon a day. They’re too busy to pollinate.

So, female zucchini blossoms – which start forming baby squash before the bees arrive – never get the attention they need from pollinators. Without proper pollination, the squash rot before they mature. This issue can happen to other cucurbits as well such as crookneck squash and pumpkins.

In these hot and smoky conditions, tomato blossoms also will dry out and whither before forming fruit, due to that combination of excess heat and lack of pollination. Tomatoes usually will not set when temperatures are above 95 degrees.

As for eating mature squash, tomatoes, peppers, peaches, grapes and other produce that you may be harvesting, wash produce thoroughly to remove any soot from the smoke. Peel if the skin feels gritty.

What crop suffers the most from smoke? Wine grapes.

Continued exposure to wildfire smoke is of major concern to California grape growers. Grapes can absorb smoky flavors, developing what’s called smoke taint. That can ruin wine grapes; experts describe its flavor as “burnt, medicinal, campfire … like licking a wet ashtray,” according to The Wine Spectator. Often not apparent in fresh grapes, those bad flavors are brought out by fermentation.


0 comments have been posted.

Newsletter Subscription

Sacramento Digs Gardening to your inbox.

Local News

Ad for California Local

Dig In: Garden Checklist

For week of March 19:

Spring will start a bit soggy, but there’s still plenty to do between showers:

* Fertilize roses, annual flowers and berries as spring growth begins to appear.

* Watch out for aphids. Wash off plants with strong blast from the hose.

* Pull weeds now! Don’t let them get started. Take a hoe and whack them as soon as they sprout.

* Prepare summer vegetable beds. Spade in compost and other amendments.

* Prune and fertilize spring-flowering shrubs after bloom.

* Feed camellias at the end of their bloom cycle. Pick up browned and fallen flowers to fight blossom blight.

* Feed citrus trees as they start to blossom.

* Cut back and fertilize perennial herbs to encourage new growth.

* Seed and renovate the lawn (if you still have one). Feed cool-season grasses such as bent, blue, rye and fescue with a slow-release fertilizer. Check the irrigation system and perform maintenance. Make sure sprinkler heads are turned toward the lawn, not the sidewalk.

* In the vegetable garden, transplant lettuce and kale.

* Seed chard and beets directly into the ground.

* Plant summer bulbs, including gladiolus, tuberous begonias and callas. Also plant dahlia tubers.

* Shop for perennials. Many varieties are available in local nurseries and at plant events. They can be transplanted now while the weather remains relatively cool.

Contact Us

Send us a gardening question, a post suggestion or information about an upcoming event.