Despite the relentless downpours and splintering winds for the past weeks, spring is just around the corner, officially marked for March 20, 2023. Whether you are a green-thumbed plant-whisperer or a brown-thumbed hopeful, here are a few features about Berkeley to keep in your back pocket as you venture out into a warmer season with a shovel and a watering can.
The plant hardiness zone map is a USDA-curated reference for gardeners to determine if a plant species would thrive in the area they are living in. Planting zones are the most helpful when working with two plant genres: perennials and non-natives. Perennial plants, as opposed to annuals, live beyond one growing season so the hardiness zone helps growers gauge whether or not the species would survive through winter temperatures. Native plant species thrive in locations their ancestors dwelled in, so it would be more helpful to take note of the hardiness zone for non-native plants. The hardiness zone for Berkeley is 10a, which indicates that the minimum winter temperature ranges from 30-35 degrees Fahrenheit on average.
Weather and Growing Season
The annual weather near the greater Berkeley region reports that the average temperature ranges from 42-72℉, with a humidity of 75% and precipitation of 0.37’’. The hottest month is August (64℉) and the coldest month is January (50℉). The elevation rounds out at about 174 feet, which indicates warmer temperatures, lower amounts of precipitation and higher air pressure with high levels of oxygen. With these metrics, we can determine the growing season. The growing season is part of the year when soil temperatures at 20 inches below the surface are higher than ‘biologic zero’, or 41℉. Berkeley’s growing season is 346 days a year, making it one of the most productive places to grow plants due to long periods of favorable conditions.
Frost dates are one of the most important factors to consider when determining when to garden because most plants do not thrive when temperatures fall too low. These dates are calculated by the NOAA National Centers for Environmental Information and represent the average date of the last light freeze in spring or the first light freeze in fall. On average, the frost dates for Berkeley begin Dec. 25 and end March 1st. Although these dates are calculated based on historical weather data and guidelines, defer to local forecasts for the most up-to-date information within your localized region because the probability of a frost occurring outside of the frost dates is around 30%. Furthermore, it’s important to keep in mind that it is always colder closer to the ground, so frosts may still occur even if the air temperatures do not fall below freezing.
Seed Starting Indoors vs Outdoors
When deciding whether to start seeds indoors (i.e. greenhouse) or to directly seed into the soil bed, the most important aspect to consider is the temperature requirements. As a good rule of thumb, plant seeds in indoor trays if they’re particularly susceptible to cool temperatures or if they have a long growing season and need a head start. These include crops like tomatoes, peppers, cauliflowers, brussel sprouts and broccoli. On the flip side, most root crops, like carrots, beets and radishes, are more successful when directly sown into the garden since disturbance poses a risk to their growth. Many online planting guides and resourceful videos (I recommend Epic Gardening on YouTube!) provide recommendations on specific crops as well.
Plants to Grow This Spring Season
There are a plethora of crops that are suitable to start growing in this spring season, whether you intend to plant seeds or seedlings. Some advisable crops to start growing by seed in March include beets, arugula, cilantro, corn, dill, green beans, okra, parsnips, potatoes, squash and zucchinis. Similarly, some crops to grow as seedlings for transplanting include basil, bell peppers, bok choy, cantaloupes, celery, cucumbers, eggplants, jalapeno peppers, lettuce, oregano, pumpkins, rosemary, sage, thyme, tomatillos, tomatoes and watermelons. The Old Farmer’s Almanac is an annual publication that provides further specifics on different crop varieties and growing timelines, so refer to it if you are looking for more tailored information!
Gardens on Campus
If you’re living in a cramped dorm room (aka. jail cell) or a dreary apartment that only gets north-facing sunlight, there are spaces for you to garden on campus! The Berkeley Student Farms coalition (BSF) is a student-led organization that oversees the gardens scattered throughout UC Berkeley. These gardening spaces include:
- Oxford Tract (located across from 1750 Walnut Street)
- Gill Tract Farm (located in Albany, CA at the corner of San Pablo Avenue and Marin Avenue)
- Student Organic Gardening Association (located at the corner of Virginia and Walnut Street, but it is temporarily closed due to a transformative period to decolonize the land)
- Guerilla Gardens (located between Barker and Li Ka Shing)
- Multicultural Community Center Garden (located outside the MLK Jr. Building)
- Fannie Lou Hamer Garden (located at the corner of Hearst Field Annex)
- Clark Kerr Garden (located next to Building 12 at Clark Kerr Campus)
- Brown’s Cafe Herbal Garden (located in the College of Natural Resources by Pat Brown’s Cafe)
As a garden coordinator at the Clark Kerr Garden and the garden beds at the Golden Bear Cafe, I can attest to the tranquility of dwelling in nature away from the onslaught of bCourse notifications and emails pinging me at all hours of the day. As long as you’re wearing sunscreen, enjoy the warm rays of vitamin D the sun has to offer and visit the budding sprouts growing throughout Berkeley to clear your mind. Your mental health will thank you for it later!