40th anniversary logo for 2020
June Tips & Events for Santa Clara County
In June, as many as a dozen species may burst their buds on a single day. ~Aldo Leopold

COVID-19 Update
  • We regret to announce we have canceled our 2021 new-Master Gardener training. One of our guiding principles has always been the safety of our volunteers and instructors. We have concluded that we cannot safely deliver hands-on, interactive training while adhering to CDC and local guidelines. The next training for new Master Gardeners will be held when conditions change.

  • All in-person classes and events are still on hold until further notice. We're starting to give online talks (check our events page for the lastest info) and are now accepting speaker requests for virtual presentations.

Big Day of Giving
Big Dig Day of Giving
 UC Agriculture and Natural Resources strives to improve the lives of Californians. Through research and extension in agriculture, natural resource management, and community development, we are your trusted source of information and a partner serving your communities. UC Master Gardeners have served communities by providing research-based home horticulture and sustainable landscaping for 40 years.

On Big Dig Day—Friday, June 5—a day to ‘dig deep to support the programs you care about’ we invite you to support the vital services that sustain our state, country, and world. Gifts of any size will have an immediate impact.

Thank you for your generous support.
🌿 June Gardening Tips 🌿
Crowded fruit (in this case apples) will remain smaller.  Photo by Laura Monczynski
June Drop
Don’t worry about small fruit falling off your trees. That’s just nature at work. The trees may put out more blossoms and fruit than they have the energy to grow to maturity. So the trees naturally drop some of the excess fruit. Although it doesn’t precisely follow the calendar, it is called June Drop because much of it happens this month. If there is still crowded fruit, do some extra thinning on your own. Try to save the largest, healthiest looking fruit, while considering the spacing. Soft fruits like apricots or peaches should not touch each other or they are likely to show some rot. Fruit that grows in clusters like apples should be thinned to two or three per bunch. And if the quantity of fruit looks like it might cause a branch to break under the weight as it ripens, you can either remove some of the fruit or provide support for the branch. Individual fruits will grow larger if they have sufficient space and energy, giving you a better crop after thinning.

More Information: Thinning Young Fruit

Photo: Crowded fruit will remain smaller, by Laura Monczynski
Kale Photo by Joe Najera
Kale is primarily a cool-season crop in our area but you don’t need to remove it when the weather turns warm. It will grow year-round and even for several years. The problem you are likely to see in the summer is that it gets buggy. If you can tolerate the giant whiteflies and aphids, you can leave it as a decoy plant to attract the pests away from your other plants and to feed the lady beetles so that they will stick around. Kale grows well in the ground or in containers and is not picky about the soil. If the plant gets too big and grows a tall stalk, like walking stick kale, you can cut off the top, remove the lower three or four leaves from the stalk, and stick it back in the ground and water it. It will regrow easily. You could also wait for the seeds and grow again from seed. It will probably be pest-free again and pleasantly edible when the weather turns cooler.

More Information: Kale

Photo: Kale, by Joe Najera
Vegetables transplanted into a raised bed
It was so unseasonably cool this spring that we were not meeting our usual criteria for transplanting summer vegetables into the ground: consistent nighttime temperatures in the fifties or above and soil temperatures in the fifties. Yet our seedlings may be outgrowing their pots. Some can be moved to larger pots before going into the ground, but there comes a time when the roots need extra space. If you’ve waited this long, it’s fairly safe to get them into the ground. (Containers and raised beds warm up earlier.) Dig a hole into which you can put amendments and a little fertilizer. Gently remove the plant from the pot, not holding it by the stem so as not to squeeze and damage the vascular tissue which transports water and nutrients for the plant. Plant it at the same level at which it was in the pot (except for tomatoes which can be planted deep), gently pack the soil, and water it right away.

More Information: Transplanting Vegetables

Photo: Vegetables transplanted into a raised bed
Pink Chrysanthemum Flowers
Mum's the Word
This is a less common but good time to plant chrysanthemums. They will have plenty of time to develop a good root system before the cold winter and are more likely to bloom perennially in your garden than if they are started in the fall. You can also start chrysanthemums from cuttings. Plant them in amended, well-drained soil, or grow them in a large container. Keep them moist but not wet. They do well in full sunshine, yet a little afternoon shade is fine in hot areas. If you pinch the growing tips as they grow, they will branch and be bushier. Otherwise, be prepared to provide support if they grow tall. Also, pinching off some of the buds will result in fewer yet much larger blooms. There is a Bay Area Chrysanthemum Society for local information and sharing.        

Photo: Pink Chrysanthemum Flowers
Photo by Scott Camazine
Asian Giant Hornets
You’re probably suddenly seeing the term “murder hornet” everywhere. But you likely have not seen an actual murder hornet. They are formally called Asian Giant Hornets. They are not in our area and it is unknown if they ever will be. They decapitate honeybees which is why they are getting a lot of attention. Bees are vital to California agriculture and our own backyard gardens. The bees face a variety of threats but the hornets are not currently on the list here. Officials are monitoring them closely in order to be able to take quick action. If you think you see one, contact the Master Gardeners for help in identification and report it to the   Santa Clara County Division of Agriculture . UC Davis-trained entomologist Matan Shemoli explains about the hornet and claims that the larvae and pupae taste like French fries.

More Information: Asian Giant Hornets

Photo: Asian Giant Hornet, by Scott Camazine
View at library presentation by Tuan Hoang
Upcoming Events
Since we don’t know when we’ll be able to resume in-person activities, we’re starting to offer online events. Keep an eye on our events page for the latest schedule.

Wed, Jun 24, 4:00 p.m.–5:30 p.m.,  ONLINE Ask a Master Gardener: Vegetable Gardening
Visit the UC Master Gardener Program website  for additional information including an up-to-date list of events and classes .

Have a gardening question? Contact our Help Desk (for Santa Clara County residents). Start by reviewing our plant  problem diagnosis tips .
  • Mon-Fri 9:30 a.m.–12:30 p.m., 408-282-3105
  • Fri ONLY 1:00 p.m.–4:00 p.m., 650-329-1356 (Closed Dec. & Jan.)
  • Or send us your question online

The University of California Cooperative Extension (UCCE) Santa Clara County Master Gardener Program volunteers are trained under the auspices of the UCCE. Our mission is to promote sustainable gardening practices by providing up-to-date, research-based horticultural information to home gardeners.

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