March Tips & Events for Santa Clara County
“My heart with pleasure fills, and dances with the daffodils. ~William Wordsworth
Monthly Tips
Quiz: What’s Growing under My Mulch?
As you pull back mulch to ready your yard or garden for spring planting, you may be surprised to see a white, fungal substance underneath. Should you be alarmed? Should you remove it? Scroll below for the answer.
Photo credit: Help Desk submission
Red wagon being used to transport tomato seedlings purchased at the Master Gardener spring sale
Photo credit: Tuan Hoang
Spring Garden Fair
Our Spring Garden Fair is back! Join us on Saturday, April 15, 9 am–2 pm for our sustainable gardening showcase, premier plant sale, and educational fair. It will be held at our parcel in Martial Cottle Park in San Jose. Shop our huge variety of tomato, pepper, herb, and flower seedlings, plus a beautiful array of succulents. We grow varieties not readily available elsewhere, selected for outstanding taste, beauty, and performance in our soil and climate. See our website for more information, including schedules of talks, tours, and activities. 
Starting Summer Vegetables from Seed
March is a great time to start summer vegetables for transplants. Seeds started now will be ready to transplant in April or May, perfect for warm-weather lovers like tomatoes, peppers, and more. On our Vegetable Planting Chart, the last column “From seed to transplant” tells you about how long it takes for seeds to grow into sturdy seedlings. Tomatoes take about 6 weeks, while zucchini can be ready in as few as 3 weeks. Plan when you want to transplant into the garden, then calculate backward to figure out when to start seeds. See more tips for successful seed starting on our website.
Photo credit: University of Maine Cooperative Extension
Growing Transplants From Seed-University of Maine Cooperative Extension
Keep Foliage after Blooms Fade
After blooming - let bulb foliage die back in place so the bulbs can store energy for next years growth - Allen Buchinski
To keep bulbs blooming each year, leave the plant’s foliage in the ground long after the blossoms have withered. That’s because the foliage — the stem and the leaves — continue to channel energy to the bulb needed for next year’s blooms. Deadhead the spent flowers to prevent them from creating seedpods. Then wait for the foliage to die back and turn yellow before removing it. Some people tie the leaves together to tidy the garden, but that’s not advised because it limits the light needed for photosynthesis. Instead, intersperse annuals to hide the foliage until it can be removed.

Photo credit: Allen Buchinski
Lawn Alternatives
Kurapia - UC Center for Urban Horticulture website
Do you have a traditional lawn? Would you like something that doesn’t need regular mowing? Something that uses less water? If you’re not ready to completely remove your lawn, walkable alternatives include California native options of red fescue and meadow sedge, as well as other alternatives like white clover, UC Verde buffalograss, Kurapia, Dymondia, and thyme. Learn more using the link below, or join us for a Low Water Lawn Alternatives presentation at the Mountain View Library on March 8; we’ll show examples and discuss how you can use them.

Photo: Kurapia, UC Center for Urban Horticulture website
Irrigation Maintenance
Check your watering system regularly to make sure it’s working properly. Sprinklers and emitters that are plugged up or misdirected can cause problems for the plants they’re supposed to water, and broken emitters and hoses waste water. Get ready for the growing season by starting a watering cycle for each zone of your controller and visually checking its operation. If you’d like help, Valley Water offers a free evaluation service for properties less than ½-acre in size. Use the link below to schedule a survey.
Adding new layers of mulch at Martial Cottle Park - Allen Buchinski
Photo: Adding new layers of mulch at Martial Cottle Park, Allen Buchinski
Quiz Answer: Mycelium
Not to worry! The white cottony or crumbly substance is mycelium, which is the intricate root system of mushrooms. The thread-like filaments are evidence that soil fungus is breaking down the mulch to release essential minerals to plants roots. It’s a normal part of the decomposition process. You can just leave it in your soil, but if you want to make your mulch last longer, you can break it up and keep the mulch as dry as possible. But any organic mulch will break down over time, so it’s good practice to occasionally add a new layer.
Upcoming Events
Our monthly 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. It takes place on the second Saturday of the month (March 11), from 10–noon. Priority will be given to questions that are emailed in advance; instructions are in the Zoom registration confirmation. Registration required.

What to Do While Waiting for Summer in the Veggie Garden, Saturday, March 4, 10–11 am, Palo Alto Demonstration Garden, 852 Center Drive, Palo Alto

Low Water Lawn Alternatives, Wednesday, March 8, 6:30–7:30 pm, Mountain View Public Library, 585 Franklin Street, Mountain View

Plant Clinic Online, Saturday, March 11, 10 am–noon, Online

Preventing Pest Problems at Seeding, Thursday, March 16, noon–1 pm, Online

Succulent Open House & Sale, Saturday, March 18, 9 am–noon, Martial Cottle Park, 5283 Snell Avenue, San Jose

Spring Prep for Fruit Trees, Saturday, March 18, 10–11 am, Martial Cottle Park, 5283 Snell Avenue, San Jose

Seed Starting Is Easy!, Saturday, March 18, 11 am–noon, Martial Cottle Park, 5283 Snell Avenue, San Jose

Warm Season Vegetable Gardening, Saturday, March 25, 1:30–3:30 pm, Online
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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