June Tips & Events for Santa Clara County
“I am more myself in a garden than anywhere else on earth.” ~Doug Greene
Monthly Tips
Quiz: What Is This Goo?
This amber-colored ooze is often seen on stone fruit (apricots, cherries, peaches, and plums), tree trunks, and branches. Do you know what it is?

Photo credit: University of Florida Extension
Quiz Goo
Female and Male flower in cucumbers
Photo: Female and male cucumber flowers, Michigan State University
Female vs. Male Flowers
Flowers have genders? Yes, some of them! The cucurbit family, which includes squash, cucumbers, and melons, has separate female and male flowers. Female flowers have a small swelling on the stem which is the ovary. It will develop into the fruit if the flower is fertilized. Male flowers simply have a straight stem. These kinds of flowers require pollinators such as bees. On the other hand, many other plants, including tomatoes, peppers, beans, and peas, have “perfect” flowers which contain both male and female parts. Those flowers can be either self-fertile or insect-pollinated.
Tomato Suckers
Pinching out suckers is recommended for areas with a short growing season (for faster production) or humid summers (to improve air circulation) or to make it easier to tie plants to stakes. But with our dry climate and long growing season, there’s no need to remove them if you’re growing tomatoes in cages. Letting suckers grow provides foliage cover to shield the fruit from direct sun, gives additional photosynthesis, and will produce more fruit. Feel free to remove interior leaves that are shaded out or turning yellow, or clip foliage as needed to make the tomatoes easier to find and harvest. But no need to pinch out the suckers.
Tomato sucker
Photo: Suckers grow from leaf axils, Cornell University
Your Garden Probably Has Aphids
Green peach aphid colony with a wingless adult and several nymphs on a leaf
Almost every plant has an aphid species that feeds on it. Aphids reproduce quickly—some adults produce 80 offspring weekly. Check plants twice a week during rapid growth. Knock off aphids with a strong water spray or prune affected leaves. If necessary, use insecticidal soaps and oils like neem or canola oil, being careful not to spray natural enemies like lady beetles and parasitic wasps. Use row covers on new plants and avoid overfertilizing with nitrogen.  Ants protect aphids, so control them. Mature plants tolerate moderate aphid populations, and biological controls often resolve the problem.

Photo: Green peach aphids affect many summer vegetables, flowers, and stone fruits, by Jack Clark
Free Compost Classes
Photo showing kitchen scraps and hands holding the compost that can be made from them
Find out how to turn your kitchen waste and yard trimmings into a rich and nutritious soil amendment through free classes offered by the Composting Education Program from the University of California and Santa Clara County. Classes teach you how to build compost piles and worm bins and how to use the resulting compost to enrich the soil in your garden and landscape. Composting not only cuts your contribution to landfills, but it also helps conserve water and builds healthy soils that store carbon to help offset global warming.

Photo: Kitchen scraps and yard trimmings can become rich compost for your garden, Pixabay
Plant Advice table at 2015 Spring Garden Fair
Photo: Plant advice table at Spring Garden Fair
Help Desk and More
Do you know that in addition to the demo gardens you can visit and the talks and classes you can attend, you can get personal advice for your gardening questions? We offer two ways:
  • Submit a question to our Help Desk. Include information such as type of plant, symptoms, and a picture or two to show areas of concern, and we’ll take a look, do some research if required, and offer advice.
  • Attend our Monthly Plant Clinic. This Zoom session lets you ask your question directly to one of our experts. Be sure to register, then follow the directions and provide your question in advance.
Quiz Answer: Gummosis
Gummosis is a general term that refers to the oozing of sap. The most common cause in stone fruit is a fungal disease called Cytospora canker. The fungus infects the tree through wounds and the sap is usually amber-colored and free of sawdust. Tree borers can also cause gummosis. In this case, the sap may contain sawdust or other debris. Mechanical injuries and sun scald can also cause sap to leak and open the tree to infection. Advice to prevent and deal with it includes following good pruning practices, protecting tree trunks and limbs from sun scald, and pruning out diseased wood past the point of infection.

Photo: Extreme gummosis on a peach tree trunk, Utah State University Extension
Upcoming Events
Our Plant Clinic Online is an opportunity to chat with a Master Gardener via Zoom to diagnose a plant problem. You can also listen and learn while other people ask questions. The Plant Clinic Online is held the second Tuesday of the month (June 11) from 7–8:30 pm, March–October. Priority will be given to questions that are emailed in advance; instructions are in the Zoom registration confirmation. Registration required.

PADG Beautiful and Waterwise, Saturday, June 1, 10–11 am, Palo Alto Demonstration Garden, 851 Center Drive, Palo Alto

PADG Open Garden Saturdays, Saturday, June 1, 10 am–noon, Palo Alto Demonstration Garden, 851 Center Drive, Palo Alto

Planting in Containers, Saturday, June 8, 10 am–noon, McClellan Ranch Preserve, Community Garden, 22221 McClellan Road, Cupertino

PADG Open Garden Saturdays, Saturday, June 8, 10 am–noon, Palo Alto Demonstration Garden, 851 Center Drive, Palo Alto
How to Establish Healthy Soil in Your Garden, Tuesday, June 11, 6:30–7:30 pm, Online Event, Online
Growing Garlic and Other Edible Alliums, Tuesday, June 11, 7–8:30 pm, Saratoga Library, 13650 Saratoga Avenue, Saratoga
Plant Clinic Online, Tuesday, June 11, 7–8:30 pm, Online

MCP Native Gardens Guided Tour at Martial Cottle Park, Saturday, June 15, 9 am–noon, Martial Cottle Park, 5283 Snell Avenue, San Jose
MCP Succulent Open House & Sale, Saturday, June 15, 9 am–noon, Martial Cottle Park, 5283 Snell Avenue, San Jose
PADG Open Garden Saturdays, Saturday, June 15, 10 am–noon, Palo Alto Demonstration Garden, 851 Center Drive, Palo Alto
Integrated Pest Management, Saturday, June 15, 10 am–noon, Eddie Souza Community Garden, 2380 Monroe Street, Santa Clara
Growing Culinary Herbs in Santa Clara County, Saturday, June 15, 10:30–11:45 am, Willow Glen Public Library, 1157 Minnesota Avenue, San Jose
Flea Control & Diseases: Starting from Scratch, Thursday, June 20, noon–1 pm, Online

SCTDG Summer Fruit Tree Care, Saturday, June 22, 9–10:30 am, South County Teaching and Demonstration Garden, 80 Highland Avenue (Corner of Monterey Road & Highland Avenue), San Martin
PADG Open Garden Saturdays, Saturday, June 22, 10 am–noon, Palo Alto Demonstration Garden, 851 Center Drive, Palo Alto
Container Gardening Basics, Saturday, June 22, 11 am–12:30 pm, Milpitas Library Auditorium, 160 North Main Street, Milpitas
Growing Tomatoes and Peppers Successfully, Wednesday, June 26, 7–8:30 pm, Cupertino Public Library, 10800 Torre Avenue, Cupertino
PADG Open Garden Saturdays, Saturday, June 29, 10 am–noon, Palo Alto Demonstration Garden, 851 Center Drive, Palo Alto
STDG Success with Succulents, Saturday, June 29, 1–3 pm, Sunnyvale Teaching and Demonstration Garden, Charles Street Gardens, 433 Charles Street, Sunnyvale
Check our calendar for the latest schedule of events. Videos of many past presentations are also available.
About Us
University of California Master Gardener volunteers promote sustainable gardening practices and provide research-based horticultural information to home gardeners. Visit our website for more information including:

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