Many self-sowing, non-hybridized (non- terminator) annuals will readily self-sow in your garden. Plant one Agrostemma githago 'Milas' this year and you will see 10 or more popping up next Spring – usually right near where the original plant was growing. Here in mild-weather coastal California, we often see some annuals self-sowing two, even three times a year for almost year around encores. Many gardeners love the free plants, which handily add excitement and fun to a barren or neglected garden – and even more so if you're a new gardener on a budget!
Now, sometimes we hear folks complaining that they never see self-sown volunteers and ask us what is wrong – where are their free plants? Let's take a look at some reasons why your volunteers could be missing in action:
Yes, those cute, little birdies do love their seed, and some of them love fresh new seedlings, easily devouring them in no time at all. Here at the nursery, we have often been plagued with adorable little white crown sparrows from November to the end of February, just when we are planting out so many Spring blooming seedlings.
Their favorite snack? Fresh sprouts of many native annuals like "Baby Blue Eyes" Nemophila menziesii,"Tidy Tips" Layia platyglossa and hardy annuals like Papavers,,Agrostemma and Malcolmia. During some Winters (just when these annuals are sprouting in mild climates), we've had to put up bird netting to dissuade those feathery little marauders and that has worked very well. This year, we've adopted a few more feral cats who live on the premises and that seems to have made a big difference – no missing or mangled plants!
Another reason you may be missing volunteer seedlings is that the birds got to the seed before it dropped to the ground. If you think that's the case, you can try planting seed-rich decoys in your garden to entice them away from plants you want to see volunteer. Yummy annuals like Sunflowers, Millet and Rudbeckias will hopefully keep them busy and sated. And don't cut them down in Fall, let the seed heads remain thru the Winter, just when the birds are extra hungry for snacks. Maybe your best bet will be to just circumvent the birds and collect your own seed to plant out after the birds have gone (ours leave by end of February). SEE BELOW for how-to seed collection instructions!
The garden's bane! Those pesky blobs of goo are voracious and the rainy season is snail season (here in California) just when so many of your seedlings will be sprouting up out of the soil. Interestingly, snails go after a lot of the same annuals that the birds love to munch on: nice, tender, Spring blooming hardy annuals that love to sprout in Fall and Winter and grow up during the rainy season in order to bloom their hearts out March thru May.
Sluggo is the best solution to snail invasions. I am not a spokesperson for Sluggo – I just find it is absolutely the most effective snail bait around. It's made from iron phosphate and is non-toxic in your garden and harmless to pets.
Now, I know it's a bit expensive but it's also totally effective if you use it regularly. During sporadic rainy weather I put it out about every 2 weeks. During long bouts of solid rain I will put it out every few days, encircling seedlings that are snail favorites. I sprinkle it on heavily –probably far more than the bottle recommends, as much as a solid ring around those tender leafed annuals. I love my babies and I want them to make it through snail season –and this ensures that they do!
Do you hire help to keep your yard nice and tidy? I can't tell you how many times I have heard sad tales of mow and blow gardeners ripping out all the volunteer seedlings because they thought they were weeds or grass seedlings. My best advice is to go out into your garden once a week, watching for seedlings, and warn your gardeners. You'll also begin to learn what they look like and how to tell the difference between a weed and a volunteer. After a few seasons, you'll have it down and hopefully so will your gardeners!
If you regularly dead-head or cut your flowers to bring indoors, make sure to leave some spent blooms for future seed pods. As long as you have some pollinators, seed capsules will soon appear.You must wait until the seed capsules become dryand the seeds ripe (dry) before collecting your seed.
One easy way to tell if your seeds are ripe is to shake one of the seed capsules. If you hear them rattling inside or see some fall into your hand when you turn the capsule upside down, you'll know they are ready to be collected. This means they are ripe and will sprout properly when you plant them. Collecting seeds before they are ripe leads to very low or no germination at all.
An easy way to collect seed from many plants is to cut the dried stems holding the seed pods and put them into a paper bag. You can use a lunch bag or paper grocery bag depending on how many stems you'll cut. It helps to hold the bag underneath the pods while you cut, so you won't lose any seeds that fly out. Afterwards, you can shake the bag – that helps the seeds fall to the bottom.
Next, when you get a chance, you'll want to inspect each dried seed capsule and loosen any remaining seeds, separating them from the capsule and stem debris. You can easily store them for up to 6 months in a paper envelope (which helps them stay nice and dry) in a cool, dry, place until you are ready to sow them. If you want to store them longer, put them in small envelopes (after they are completely dry) and then into a glass jar in your refrigerator to keep them viable.
If you have collected seeds from Spring blooming California native annuals or cool season growing hardy annuals (which also bloom in Spring ), you can sow these anytime in your garden between October and February 15th in coastal Northern California. You folks in Southern California should sow them before January, as your Spring season is earlier than ours. For extremely cold inland and mountainous areas, I recommend waiting until February or until the ground is no longer frozen. If you have hard-pan clay soil you'll want to amend it first, digging in a good "planting mix" (not potting soil) to at least 10 inches deep, so the roots have somewhere hospitable to grow into and the seeds will not just run-off with the rains.
You can just toss them out or lightly scratch them into the soil – no more than ¼" deep. After that, make sure they stay fairly moist. If it stops raining for more than a few days, you'll want to water your seeded area especially after the seeds have germinated. Tiny seedlings will quickly die without moisture.
Alternatively, you can plant your seeds in empty pots, 6-packs, pie plates, etc. and keep them moist in a bright but not too sunny area (baby seedlings in containers can easily dry out in the full day sun). "Potting Soil" is preferable for seed sowing, as it is light and fluffy, allowing seeds to germinate more freely. Again, you can scratch them in to a depth no more than ¼". When the first true leaves appear (after the first two immature leaves), you'll want to thin the seedlings out to about 1" apart. After they reach about 1" tall, it's best to plant them in individual containers. Again, I highly recommend that you use a "planting mix" as opposed to "potting soil" at this stage. "Planting mix" contains more nutrients and will retain water much better. Once the seedlings reach 2-3" tall (this will happen pretty quickly), they are ready to be transplanted out into the garden. Make sure they get enough water and never dry out or they will either die or become rather stunted and unhappy. After a few days, it's an excellent idea to surround them with a bit of good compost – up to 1". This will always give them a good boost and a great start in life. Just be careful not to push the compost right up against any stems or it will rot them. If it's slug and snail season, you know what to do. Surround them with Sluggo snailbait.
Good Luck and Happy Gardening!