Stratify, sow, sprout, succeed

This guide, written by Carson Trexler and edited by David Fefferman, focuses specifically on sowing Sarracenia seeds in winter and getting them to germinate in the following spring, but the same care for Sarracenia seeds and seedlings applies to nearly all temperate carnivorous plants, stratification included. Also, if you’re interested in how to make pitcher plant hybrids of your own, check out this handy guide on Sarracenia hybridization we recently published.

Growing plants from seed is about as rewarding and fun as it gets! Unlike vegetative propagation, many seed-grown plants are genetically unique, meaning that a huge array of colors, shapes, and sizes are possible from seed-grown plants.

I recommend for folks who’ve never kept North American pitcher plants before to start with an adult plant first. Growing Sarracenia from seed can take a long time. It takes nearly four years after germination for even large, fast-growing plants to get big enough to flower. Also, the likelihood of germination is naturally probable, but ultimately unpredictable. You may be unable to get your seeds to sprout (try to wait at least 5 or so months before giving up on seed which you’ve already sown). But if you’re determined to start out with seeds, it shouldn’t be too difficult for you to keep them, especially if you’ve kept a temperate wetland plant before.

As seedlings are tiny and vulnerable, they will die if subjected to simple mistakes (like under-watering) that wouldn’t normally kill an adult plant so fast. In this way, seedlings are somewhat unforgiving.

That said, juvenile Sarracenia are themselves fascinating and joy to keep. Having a horde of seedlings can be just as fun as having a big collection of adult plants. Plus, with each new seedset, your collection changes each time!

Looking for Sarracenia seed to grow your own? Check out some of the fan-freaking-tastic Sarracenia hybrids offered by vendors in our marketplace:

3.5-Step Instructions for Germinating Sarracenia

You don’t have to do it all this exact way, but this method achieves all the requirements and is pretty efficient:

0.5 Cold stratificationSarracenia seeds require a period of cold, damp conditions similar to winter for about 6-8 weeks before they can germinate. In a temperate climate, seeds exposed to the elements and kept on damp soil will germinate in spring. This pattern of growth is exactly the same as that of adult plants, which are dormant in winter and grow again in spring. If you live in a temperate climate and can pull off stratifying seed outdoors, skip to step #1.

If you live in a warmer or tropical climate with mild winters, or if you plan on growing your seedlings indoors, you’ll have this extra step of stratifying seed manually. A great method for Sarracenia stratification is to dampen a paper towel with reverse osmosis water, scatter the seeds across it, cover the seed with another moistened paper towel, and place this in a plastic bag or Tupperware container in the refrigerator. Leave them here, mostly undisturbed, for the 6-8 week period.

If a little mold forms on the paper towels, don’t stress it. Mold shouldn’t have a negative effect on the seeds themselves, but be sure to use fungicide after sowing them on soil. Remember to label your bag with a sharpie, and include a plastic label inside the bag should the sharpie wear off. Above all, remember to write the date!

1. Sow your seeds any time in mid-winter (around 8-9 weeks before last frost) on a medium of wet sphagnum peat – avoid perlite or other inorganic substances so the tiny roots will have access to water. To conserve space, use a large container. A four-inch-wide pot can fit about 20 seedlings for the first two years of their lives. Be careful to space your seeds about 1 centimeter apart so they do not immediately compete against each other. Do not cover your seeds with soil, and do not fill the pot up to the brim with peat! Leave about 1/2 inch between the soil line and the rim of the pot so water won’t wash away your seeds. If fungus is a concern, spray liberally with a sulfur-based fungicide weekly.

2. Place the pots outside in mid-winter, but protect them from heavy rain or fallen leaves, or else the seeds may wash away or get covered up. You may want to keep a large humidity dome or screen over them for the express purpose of keeping debris out. Keep the soil wet by placing the container in a tray of water, just as you would your other temperate carnivorous plants. Remember, North American pitcher plant seeds require a period of cold and wet conditions to germinate – just as they would experience in the wild. If necessary, spray for fungus using a sulfur-based fungicide.

3. Wait until spring to see germination. Seeds may sprout at any time in spring, so keep an eye out and don’t throw them out too soon!

After germination, treat your seedlings as you would adult Sarracenia. There is no difference in care between adult and juvenile plants. Sprouts are as cold-hardy as adults, as long as they experience seasonal fluctuation to prepare them for cold weather. However, because of their small size, seedlings dry out very quickly, so it is important to pay attention to the water levels in their trays. 

When seedlings go dormant, all their leaves may die off. Fear not, for what looks like an empty pot will revive in spring.

You can fertilize Sarracenia seedlings, especially if grown under intense artificial lighting, to quicken growth. We’ll cover this topic in a future post.

Continuing Care

It is wise to separate your seedlings once they’ve gotten 7 to 8cm (3+ inches) tall. At this point, the soil is probably overcrowded with roots and competition between dense plants can kill whole masses of seedlings. Mold, if it gets into such an environment, can kill your project with devastating speed. I recommend dividing your plants into single 1-inch wide, 2.5-inch tall rose pots, or into group pots over 4 inches wide, with one plant allotted per diameter inch (for example, a 4-inch pot can house 4 seedlings, a 6-inch pot can house 6 seedlings, etc.). Once rhizomes are 3/4 inch wide the plant should be given its own 4-inch pot.

Sarracenia do not require high levels of ambient humidity. Though their rate of transpiration is fast, their hydration needs are met entirely by their roots. It is not necessary to keep Sarracenia seedlings in lidded containers. Such containers are crisis prone. Lidded containers can take a moldy turn in an instant. The most important aspects to master before tinkering with ambient humidity are the more essential elements of water and light.

Enjoy growing!