Succulent seed sowing for the beginner
Succulent Seed Sowing
Australia’s nearly impossible and unbelievably expensive import laws make growing from seed an attractive option for adding new, desirable plants to your collection!
So, Why Sow?
Is sowing seeds better than propagation via cuttings or leaf? Well, I have a little insight. I prefer taking cuttings over growing succulents from seed for a couple of reasons. First, they establish faster. There’s nothing as simple as taking a cutting, sticking it into some dirt, and checking back a week later to find roots and maybe some new growth. Another advantage is that they are exactly the same as the parent plant, which may have been chosen by a breeder as being a superior clone to its many siblings. But seeds do have an advantage! Seeds are diverse, and like a family of humans, all the kids are just a little bit different. They all have common traits that make them recognizable by their parents’, but each stands apart from the next. Buying seeds might get you a species you have never seen before, then you can select the best form after they’ve been growing for a few years, then propagate the most interesting plants from that selection. This is how I get the best specimens from our greenhouse!
Cleaning some large discorea seeds.
Where to Get Succulent Seeds
You can get succulent seeds from many different sources: you can harvest them from your own collection, maybe you’re working on your own cross pollinations to develop hybrids; or a friend has a flowering specimen and they’re nice enough to throw a few seeds your way; or maybe you’ve been online eyeing that rare beauty you’ve been dying to get your hands on.
If you’re buying seeds, they should be bought from a reputable dealer who knows what they are doing. Most people who have bought on Ebay, Etsy, or somewhere from China, end up being duped and disappointed. Who has seen those amazingly coloured photos of unreal succulents with bright blue, pink, purple, and brilliant red? It’s like they are straight off an Avatar-like planet. 100 multi-coloured seeds for just $10 will surely bring disappointment. They are generally alfalfa seeds or some other vegetable or grass. And sometimes, they are old and not viable, and many rarely grow. It’s best to buy from a known, recommended source.
Some Recommended Succulent Seed Sources
Import Rules for importing Succulent Seeds
Be aware of the current policies set by the “Department of Agriculture and Water Resources” (this name changes with every change of government). With department amalgamations, they spend more money on updating letterheads than managing quarantine and BICON updates, and our mismanaged water resources are responsible for the recent massive fish die offs by overselling water for agriculture. But, the Department, as I call it, has strict requirements for seed import:
Here is a complete list of requirements for importing seeds
- Parcels containing seeds must be clearly labelled “Attention Quarantine”, otherwise they will be missed, and get through unoticed
- All seeds must be in a clear packets so the seeds can be seen.
- Seeds must be pure and clean of any plant material and seed pods.
- New seeds are considered sterile.
- A declaration from the supplier is required. It should state that the seeds are commercially and professionally grown and packed, and that they are all true to type and name. Your supplier will need to prepare this. Be sure you supply this form for the supplier in advance as no one else in the world needs this form, or knows what it’s for.
After jumping through these hoops, it’s very possible that the Department will want to get their grubby hands on them anyway. Packages of seeds spill and labels are mixed up during these “professional” checks. It wouldn’t be so bad if it ended there, but it doesn’t! Fees quickly tally up when they charge $50 per 15 minutes for their “professional services”. By the way the Department runs things, it seems to me that they don’t want any seed or plant imports coming into the country. I could go on about the Department for ages, but it’s best we get back to the topic we really want to discuss, seed growing!
Where to Begin
Succulent seeds are notoriously small and range from pellet-sized to as fine as dust! There are different forms of distribution, some are windblown and others are released by rain. Dioscorea seeds are winged, and perfectly formed to fly, while Echeveria have very fine seeds that are distributed by both wind and water. Lithops are disseminated as the pods remain tightly shut until rain drops hit them, then they burst open and splash away. Very fine seeds will find small crevices to nestle into where moisture can collect to initiate germination, and enough residual spring or autumn rain sustains a new young plant. Depending on the type of seed you’re sowing, try to emulate these processes.
Discorea elephantipes seeds. Some very small Echeveria seeds.
Some Basic Rules
It is best to keep your seeds in a cool environment that is very dry. Any moisture can set off germination, even if you’re not ready. We collect a fair bit in our greenhouse, so I use envelopes to store new succulent seeds. On the envelope, I note what the seeds is, whether it is clean or not, and when it was collected. Similar notes should be kept later about the germination rate, how long it took to grow, and when it is ready for transplanting. Use your successes as a guide for future sowing!
Fine seeds go on top
Very fine seeds need to be sown on the surface of the soil. Moisture levels must be maintained as the new root radicals of such small seeds can dehydrate very easily.
Fungicides are essential
Use of fungicides in the first month or so is very important if you’re not sterilizing your soil mixes. The newly sprouted seedlings will be in a moist, humid environment for some time where fungal and botrytis pythium wilts can take a toll on these young plants.
Seedling boxes should be covered
In our greenhouse, we use polystyrene boxes which we have cut glass lids to fit perfectly on top. For smaller greenhouses and in-home gardens, a takeaway container with a lid will work. I visited Mr. Nishi in Japan where he grows his annual new Haworthia crosses in hundreds of round takeaway containers. This is how he grows crops of thousands upon thousands of his own new hybrids under grow lights with about 7–8,000 lux (about half the sun’s value).
Kayo and Mr. Nishi look at his new Haworthia seed crop.
Succulent seed sowing methods
I use about 150mm deep polystyrene boxes that are cut flat so they seal well with a sheet of glass on top that’s cut to fit. I fill the box half to two thirds full with soil. This allows room for plenty of air circulation and space for labels. With fine seeds flatten the mix, then put on a very thin layer of 3 mm washed gravel or river sand. Then sift out any seed husks or stem bits to get just the seeds. I find seed husks and stems seem to attract fungus as they decompose, which can then infect your new seedlings. Mix the seeds with a small amount of a spreader—that’s what I call it. It’s a very fine sand, similar in diameter to the seed. Mix a 10 to 1 ratio of spreader to seeds. This gives you the opportunity to spread the very small seeds more evenly over a much larger area than you could with the seeds alone. Then apply this mix over the 3mm gravel. The seeds and fine sand will fall between the cracks in the gravel, similar to the process in nature. This helps to hold it in place, offers support to very small seedlings, and creates a small micro-climate that holds more moisture than on open flat surface. Also these larger grains of sand help reduce water wash later on, where young seedlings may be washed away or ungerminated seeds washed to another end off the box.
I use this method with any size seeds. Make a groove in your seedling flat with something like a bamboo stick and sprinkle a pinch of seeds along that line. Fill it with some 3 mm gravel and some fine sand to finish covering the seeds. *Please note* Larger seeds should generally be planted at twice the depth as the diameter of the seed. This is a basic rule to follow for all seeds of a larger diameter.
Young seedlings need low light to start
Imagine a new seed falling into a rock crevice, sheltered from the elements. Full light is too harsh for seedlings, so the light needs to be dampened. You can use a piece of newspaper or shade cloth. Most succulent lovers would have some shade cloth about if they truly love their succulents! Personally, I prefer shade cloth because there are many varying degrees of shade you can get from it: about 25% to 75% shade. This is a good way to slowly introduce the seedlings to full light. Put the cloth over the glass top for a week or so under grow lights, then remove it so it’s just the glass diffusing the light. About a week later remove the glass for part of the day to harden up the plants a bit. After one more week, move them to a shady part of the glasshouse and start to slow down the watering a bit.
Watering your new seedlings
You do not need to water a sealed container for the first week of growth while the lid is still on. I use a small, extremely fine rose for watering succulent seeds. You can also use a mister bottle to give them a light spray. Don’t water heavily, just a light wash, as you don’t want the new seeds floating around and collecting in one corner of the box. The other safe way to water succulent seeds is to sit your trays in a shallow bath, shallower than the soil depth in your seedling tray, and give them a water. This works by capillary action, allowing the water to soak up through the soil to the new roots. Seeds are happiest at about 15–25° C and moisture levels should stay optimal at these temperatures. I feel it’s best not to get any part of the young plants wet for a week or two until they begin becoming hardy by introducing them to more air and light. Once they have rooted well, you can start watering more normally. Keep it light, but more frequent than your older plants.
Seed boxes covered with glass under lights lower right.
Some materials I find useful
Every country has its own individual products and climate, so here I am going to mainly talk about what’s available and best in Australia.
Here, the basic potting mix is made up of several sizes of well-rotted pine bark with added sand (I use washed river sand) then I add the same amount of 3 mm gravel to give the soil air pockets. This is the basis of my mix for seed sowing, but I also like to add:
- Coir (sieved, crushed coconut fiber)
- Peat moss
- Some fine perlite or vermiculite
All of these products are fine and light. They hold air for porosity but are soft and open to allow young roots to travel easily down to where there is more moisture and temperatures are cooler and hold just the right amount of water.
Young 2-month old Lithops seeds sown into 3mm gravel. It only took 7 days to show their new green caps.
10 Common Seed Sowing Questions, Answered
1- What is the best temperature to grow succulent seeds? = about 15–25° C
2- How long do seeds take to germinate? Most fine seeds take between 4 and 7 days, while larger seeds can take longer. And some stragglers will be germinating weeks later.
3- How often should you water? You don’t want to let them dry out but don’t drown them either.
4- Do succulents make seed? Yes, all flowering plants have the ability to produce seeds if they flower and are pollinated.
5- How much light does succulent seedlings need? Between 25 and 50% of the sun’s light. Under the plant bench is a good place to start them.
6- What soil mix should I use? A light, open but fine mix that has some water holding ability. Not just gravel.
7- When should I transplant my seedlings? This comes down to personal preference. I like to be able to hold them when transplanting them, so I feel they are large enough once the get 4 to 6 leaves. Any younger, and they are easily damaged. Lift them out with a small spatula to get as much root as you can with minimal damage.
8- When is the best times to sow seeds? Spring and autumn, unless you have a temperature controlled room. Summer in Australia is too hot, and winter is too cold.
9- What is the best method for watering seeds? Dip your container into a larger dish of shallow water and allow the soil to soak up the water. It’s best not to get the young leaves wet.
10- Is it easy to grow succulent seeds? Yes, just follow the rules and principles above!
To learn more about The Department and how it effects the business of plants visit their website, or read my thoughts below.