Milkweed for Monarchs

We often meet visitors in the gardens who would like us to point out the milkweed plants we have growing here at Marin Art and Garden Center. With the critical situation of the Monarch butterfly population on our minds, many of us would like to help these long-distance travelers find a reliable food supply for growing caterpillars to support their species’ survival.

Monarch butterflies are famous for their annual migration; here in the West, butterflies mainly from Oregon and Nevada spend the winter along the coast from Mendocino to Baja California in Mexico. Their winter requirements are quite specific: sites must feature dappled shade, high humidity, a source of fresh water, and temperatures above freezing for the season. They also need a food supply, and while adult butterflies feed on late-blooming flowers, Monarch caterpillars only eat milkweed; in fact, the monarch butterfly is also known as the “milkweed butterfly.” But these plants are rapidly disappearing, due to the loss of habitat stemming from land development and the widespread spraying of weed killer on the fields where they live. 

Planting milkweed in your home garden is easy and rewarding, but be prepared: Monarch caterpillars are eating machines and each one will mow through about 20 leaves. So make sure you have enough milkweed plants or the caterpillars will starve!

If you’re planning to grow milkweed in your garden, there are a few considerations to take into account. Milkweed plants are food for caterpillars but poisonous to humans. Do not get milkweed sap on your skin or in your eyes. Milkweed is also toxic if eaten, so keep plants away from young children and pets.

There are many varieties, some which thrive in full sun, some in humid conditions, and some even in very dry conditions. To find out more about the various species of milkweed and which are best for your area, check out this factsheet courtesy of Monarch Joint Venture. Milkweed seeds can be very slow to germinate and do take some time and patience. For best results and to speed up the germination process, place the seeds in wet paper towels in a plastic bag in the refrigerator for 30 days prior to planting. Then plant the seeds in a sunny place about ½” deep and water them for at least two weeks.

After about two months, your milkweed plant will be big enough for caterpillars to eat. As a perennial, they will come back every year, but in the autumn, you should cut back the plants. It’s also important to cut back the milkweed to encourage migration; although there are overwintering sites in Marin, it’s best for the butterflies to be in a frost free location. Also, the more butterflies that overwinter in a single location, the greater the genetic diversity, so it’s better for them to congregate in larger numbers.

In this video, Garden Manager Steven Schwager explains how to cut back milkweed, for the best health of our Monarch visitors.

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IRS Guidelines for Gifts from Donor Advised Funds to Support MAGC Events

Thank you for your interest in giving to the Marin Art & Garden Center events from your Donor Advised Fund (DAF) or Family Foundation.

We sincerely appreciate your generosity and support!

To ensure your gift follows the current IRS guidelines for DAF/Family Foundation support of an event, we would like to share the below guidelines with you.

  • Raffle tickets, tickets to galas and other special events, auction items, and benefits conferred in connection with a DAF/foundation grant are not permitted.
    • IRS has specifically ruled that fair market value associated with fundraising events cannot be separated, a practice known as “bifurcation.”
      • For example, with Edible Garden, if the price of the ticket is $200 and the FMV fair market value (non-tax-deductible amount) is designated to be $50, the donor must pay from sources other than her DAF/foundation for the full value of the ticket ($200) and not just for the non-tax-deductible amount ($50).
    • We recommend you confer with your financial advisor to confirm if any of these examples of how donors may still use their DAF to support an event would work for you:
      • A donor could sponsor the event, and not attend, and pay fully out of the DAF/foundation.
      • A donor could sponsor the event using DAF/foundation funds and attend by purchasing an individual ticket through non-DAF/foundation funds.
      • A donor could sponsor the event, join the event as a guest of another donor/table guest, and pay fully out of the DAF/foundation.
      • A donor could sponsor the event and host the afforded number of people at their chosen level as long as they pay for the seats at the lowest ticket price ($200 for Edible Garden) outside of their DAF.
        • As an example, a $1,500 sponsor that covers 2 guests, could pay for their sponsorship with $400 from a different source of funds, and then give an additional gift of $1,100 out of their DAF.


Please email Tod Thorpe, Director of Development at to discuss your gift to Marin Art and Garden Center