Cutting back poppies and harvesting seed

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I received an email requesting more info on how to cut back California poppies (Eschscholzia californica) so that they bloom again. This is what my poppies do through the bloom period and how I handle it.


After poppies have bloomed for a while their stems become very elongated and the leaves and stems turn powdery and grayish. I don’t think this is mildew because it happens even when there is no additional water.


Anyway, at this time there are usually flowers and ripe seed pods. You can tell the seed pods are ripes because they turn brown and grooves form lengthwise along the pod.


One of the grooves will become darker. If you open the pods, the mature seeds will be dark brown while immature seeds are green.


On a warm day when the seeds are rip the pods pop open spewing the seeds around. The spontaneous opening of seed pods is called dehiscence. When they pop open it is described as explosive dehiscence because it doesn’t just gently open, it actually pops propelling the seeds so they cover a larger area. I harvest the seeds when I see the grooves, placing them in a paper bag. Over time the pods pop and are collected in the bag. If you do this, make sure the bag stays dry and check it often for insects (notice the earwig chowing down on my seeds!).



Now back to cutting the plants back. Poppies are actually short-lived perennials. The same plant can live for a few years, though since they reseed so easily it is hard to keep track of who is who. Once they have bloomed, turned gray, and developed mature seed pods, I cut them nearly to the ground. I have a lot of poppies so I do this quickly and carelessly. In fact a weed whip or lawn mower with the blade set high would work.


You can tell this will work because the plant often sends out new leaves near the base of old stems.


I harvest the seed pods and compost the plant.

Here’s a group of poppies that are ready to be cut back. Even though they are still blooming the foliage is gray and seed pods are maturing.


Sometimes I cut them back more harshly than this, but either way works.


Here’s the pile of foliage that I throw into the compost pile after collecting the nearly ripe seed pods.


Below is a plant that was cut back a few weeks ago. The foliage is green but you can see old stems among the new growth.


And finally here is a poppy that is blooming again. Usually they don’t bloom as profusely later in the summer and often the flowers are smaller.


If anyone does it differently or has something to add, please comment.

16 thoughts on “Cutting back poppies and harvesting seed

  1. This post is just wonderful – I was wondering how to go about this little job. Thank-you so much. The step by step instructions are nice and clear, and I feel confident I can now seed collect and cut back my own poppies!

  2. RV

    Thank you for a thorough explanation, especially with pictures in different stages.

  3. Lorraine

    good and to the point instructions, Barbara. I did some cutting on mine today but I wasn't paying any attention to the seeds pods. I guess I had better take a look at them.

  4. Yes, that's what I do, though I usually pull some as well. I always have more than I could possibly want…But they are so pretty in spring!

  5. I'm interested in your comment that the white coating isn't mildew, as I'd always assumed it was. If it's something else I could see how a whiter surface color might reflect the light better than green leaves, giving the plants an edge in brighter, hotter weather. Still, the color change always seems to take place when the plants are about to decline for the season.

  6. Lovely post and great pictures – thank you. I haven't grown California poppies before but always admired them (I shall definitely plant some this year). Didn't realise they had such long pods and were so far removed from the papavers.

  7. James, when the Salvia gets mildew it is blotchy and related to moisture. I&#39;m just not sure about the poppies. Guess I show have a look under a microscope.<br /><br />TM, I save the seed for kids to throw out in the Nature Park. You&#39;re right – way too many for my garden alone. <br /><br />Thanks to all others for comments.

  8. James, interesting comment, I wonder if that could be true. And you&#39;re righ, Barbara, a microscope would show. Or maybe your count ag agent would know?<br /><br />I&#39;m abashed to confess that I live in N. California and you&#39;ve taught me something about my local wildflowers. I&#39;d seen them re-blooming in other people&#39;s gardens, and always just assumed it was because they watered

  9. I have a large wild garden on the south side of my cottage and the ca.poppies have gotten so lush and beautiful over the years but it is July and they have gotten grey and flowers are almost all gone and I wondered if I could cut them back and they would bloom again. I looked all over the net and found your wonderful explanation thank you so much heading out to cut them back tomorrow. Lovely,

  10. Dave S.

    Great pics and explanation. Have been wondering about the appropriate timing for this and your blog work here is greatly appreciated.

  11. Anonymous

    The grey color IS mildew, pure and simple. The reason they have mildew is because you, like nearly everyone it the state it seems, are sowing non-local poppies. In my part of CA (coastal Santa Barbara), the local genotype is distinctly yellow and orange flowered, has different leaf morphology (shape), is a pronounced perennial, and is very, very resistant to powdery mildew. Too bad everyone and

  12. Thanks for the info, anon. I&#39;d be happy to grow local native E. californica but cannot get them. Probably one of the problems is the low germination rate of wild poppies due to seed dormancy. The other problem is getting the seed from the wild, here in urban LA County. <br /><br />Collecting a few seeds in the wild can be problematic too since populations are already stressed and with so many

  13. Anonymous

    That was soooo helpful – thank you!

  14. Anonymous

    Wonderful explanation especially with the photos. The pictures convey so much more information. Mahalo (thank you) for being a teacher.

  15. Hello. I was in Lancaster, California, in the Antelope Valley, only about two hours from downtown LA a few years ago during their annual California Poppy Festival. There is an area of many square miles, maybe 30, outside of town that is called the California State Poppy Preserve. When seen from 20 miles away during blooming season the entire area is bright orange and nearly unbelievable! I took

  16. Dear Eral. Even in large areas it is best not to harvest seed. I&#39;m pretty sure a permit is required. It seems like it wouldn&#39;t matter but if a lot of people do it, they can have a negative impact. Also, according to Curtis Clark (expert on Eschscholzia) native seed has dormancy built into it so a lot of the seed won&#39;t germinate in garden conditions. This has been bred out in the seed

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