July Tips & Events for Santa Clara County
“It's difficult to think anything but pleasant thoughts while eating a homegrown tomato." — Lewis Grizzard
Tomato russet mite damage UC by Jack Kelly Clark
Healthy Tomatoes
Tomatoes are one of the most popular vegetables in home gardens, largely because of the taste difference between a homegrown tomato and a store-bought tomato. Here are a few things to watch out for to keep the plants healthy. Regular watering helps nutrients flow throughout the plant and can prevent blossom end rot . Clean soil and sanitation reduce the common Verticillium wilt in which lower and older leaves turn yellow and brown. And russet mite , where lower leaves and stems appear a greasy bronze, can be controlled with sulfur dust.

Photo: tomato russet mite damage, UC photo by Jack Kelly Clark
Dahlia blossom UC photo by Cheryl A. Reynolds
Encouraging Dahlia Blooms
First, make sure those tall flowers have support so they don’t flop over or break off. Disbudding—removal of all but the central bud on each stalk—will result in larger more spectacular flowers. Deadheading—cutting the spent flowers back to one node below the bloom before they can set seeds—will encourage lateral blooms. Water the plants regularly, and continue to apply low nitrogen fertilizer throughout the summer.

Fundamentals of Growing Dahlias , American Dahlia Society

Photo: UC photo by Cheryl A. Reynolds
Tree turns in landscape UC photo by Jack Kelly Clark
Watering Trees
The amount of water trees need in the summer depends in large part on the age of the tree. Newly planted trees with shallow roots may need weekly water. Trees that are a few years old and fairly well established may need monthly watering. Mature trees with extensive root systems may not need any supplemental water. These are just VERY general guidelines. It is essential to know the water requirements of the plants. You can determine these by researching cultural needs or knowing their native habitats, the soil type and how well it retains water, and the microclimate in which the tree is located, e.g., shaded, windy, dry. The UC WUCOLS database has information on the water needs of over 3,500 plants used in California landscapes. Always water slowly and deeply to penetrate down to the roots.

Photo: UC photo by Jack Kelly Clark
Blueberries UC Bug Squad photo by Kathy Keatley Garvey
Depending on the variety, you may be harvesting blueberries from your garden right now. Yes, there are several varieties of blueberries that do well in our warmer climate, with a little extra care. They all need regular water and well-draining soil with a lower pH than our local native soil. Adding elemental sulfur is a good way to acidify the soil. Harvest blueberries on almost a daily basis, especially if you want to beat the birds and squirrels to the ripe berries. The blueberries are ready to eat when they are uniformly blue/purple, even on the bottom. They should come off easily with a slight tug.

Photo: from UC Bug Squad Blog, by Kathy Keatley Garvey
Brussels sprouts with leaves removed ready for harvest by Allen Buchinski
Brussels Sprouts
Why would anyone want to grow Brussels sprouts? Well, for one thing, they look really cool growing. And having it fresh from the garden may be your best chance to get your family to eat it. The cooler coastal regions of California are where they grow best, so if you have a cooler microclimate you may have a chance with this vegetable. Plant from seed or transplant, twenty-four inches apart in well-drained soil. Fertilize initially and keep the soil moist. Harvest the vegetables when they look and feel like firm tiny cabbages, about an inch in diameter, but before they split.

Photo: by Allen Buchinski
Visit or subscribe to our blog  for longer articles on seasonal topics
 Ask a Master Gardener Booth by Tuan Hoang
Upcoming Events
We offer free or low-cost gardening talks, workshops, and courses all over the county, as well as hosting information tables at many community events. Please join us and bring your questions!

Palo Alto Demo Garden Open Saturdays from 10 a.m.–noon (May–Oct)
Come see what we're growing at our  edible and water wise gardens   and get answers to your gardening questions. Feel free to bring plant pests or disease samples for identification. We're located at Eleanor Pardee Community Gardens, on Center Road near Martin Street,  Palo Alto   (v iew map ).

Sat, Jul 06, 10:00 a.m.–11:00 a.m.,  Keeping Your Vegetable Garden Healthy and Productive , Palo Alto Demonstration Garden, 851 Center Dr,  Palo Alto

Sat, Jul 06, 1:00 p.m.–2:30 p.m.,  How to Compost at Home: Dos & Don'ts , Central Park Public Library, 2635 Homestead Rd,  Santa Clara

Tue, Jul 09, 7:00 p.m.–9:00 p.m.,  Spice it Up: Growing Garlic, Ginger & Chives , Saratoga Public Library, 13650 Saratoga Ave,  Saratoga

Tue, Jul 09, 7:00 p.m.–8:00 p.m.,  Pesky Vertebrate Pests in the Garden , Campbell Library, 77 Harrison Ave,  Campbell

Sat, Jul 13, 9:00 a.m.–11:00 a.m.,  Flower Cutting and Arranging Workshop , Martial Cottle Park, 5283 Snell Ave,  San Jose

Sat, Jul 20, 10:00 a.m.–11:00 a.m.,  Gardening for Pollinators—A Walk and Talk , Martial Cottle Park, 5283 Snell Ave,  San Jose

Sat, Jul 20, 1:00 p.m.–3:00 p.m.,  Veggies in a Pot for When Summer is Not , Sunnyvale Teaching and Demonstration Garden, Charles Street Gardens, 433 Charles St.,  Sunnyvale

Sat, Jul 27, 9:00 a.m.–11:00 a.m.,  Flower Cutting and Arranging Workshop , Martial Cottle Park, 5283 Snell Ave,  San Jose

Wed, Jul 31, 7:00 p.m.–8:30 p.m.,  Composting With Worms , Los Altos Library, 13 S. San Antonio Road,  Los Altos

Sat, Aug 03, 10:00 a.m.–11:00 a.m.,  Less Work- More Food: The Joy of a Productive Fall Vegetable Garden , Palo Alto Demonstration Garden, 851 Center Dr,  Palo Alto

Sat, Aug 10, 9:00 a.m.–11:00 a.m.,  Flower Cutting and Arranging Workshop , Martial Cottle Park, 5283 Snell Ave,  San Jose
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.

The University of California prohibits discrimination or harassment of any person on the basis of race, color, national origin, religion, sex, gender identity, pregnancy (including childbirth, and medical conditions related to pregnancy or childbirth), physical or mental disability, medical condition (cancer-related or genetic characteristics), ancestry, marital status, age, sexual orientation, citizenship, or status as a covered veteran (covered veterans are special disabled veterans, recently separated veterans, Vietnam era veterans, or any other veterans who served on active duty during a war or in a campaign or expedition for which a campaign badge has been authorized) in any of its programs or activities.

University policy is intended to be consistent with the provisions of applicable State and Federal laws.