The genus Byblis is overall an underappreciated group in the carnivorous plant realm, but even within the rainbow plants there are a couple that really don't get quite the attention they should. Even though every time someone posts one in its fully glory the reactions skyrocket....
The two perennial species found in Southwest Australia are unusual even amongst their odd brethren, and this one, in particular, is the rarer of the two both in the wild and in cultivation. Byblis lamellata is found along the coast, a lover of white sand plains or open, sandy-soil woodlands that occasionally flood during the cool, wet winters of this Mediterranean climate and frequently turn bone dry in summer. It's the same region from which hail many of the pygmy and tuberous sundews that are also highly coveted but sometimes irritatingly touchy to grow; in my experience, the perennial rainbows once sprouted are nowhere near as troublesome. This species is found slightly further northward than its close cousin B. gigantea, generally north of the city of Perth while the other species is mostly found around and south of same said city, and in possibly slightly drier environments overall though they share a similar niche.
B. lamellata grows to an average of 60 cm (about 2 feet) tall when it is fully mature, slightly larger than its more southerly cousin; plants start off as rosettes of foot-plus long leaves that splay out from a central point, but as they age those rosettes begin to rise on chunky stems to form towers of leaves that reach in all directions and sometimes branch to form miniature woody bushes. Each leaf is covered on the underside (more or less, as they reach out in all directions from the leaf) with simple, stalked tentacular glands bearing a drop of sticky mucilage at the tip, waiting for som unlucky small insect to land on them. If this happens, the "dew" sticks to the insect and bogs it down, and the struggles of the prey will over time trigger the base of each touched gland to wilt, bending it inward toward the surface of the leaf and toward other glands that ensnare and eventually either exhaust or drown the hapless insect against the leaf. Then at night, smaller glands on the leaf surface will secrete fluids containing digestive enzymes to cover the prey, breaking down what compounds the enzymes are meant for and then reabsorbing the resulting solution as day breaks again.
Often the plant isn't using its own secretions alone either; many rainbow plants and sundews in Australia play a sometimes commensal, sometimes mutualistic symbiotic part in hosting various species of Setocoris assassin bugs, which can manage to maneuver around the tentacles without getting trapped and feed on the other hapless insects who do not have this superpower. They then in turn release nutrient-rich frass (insect poop for the less fancy) that the plants can break down and absorb things more easily from.
Each year the plants run through seasonal cycles, waking up as the winter rains return and sprouting from old rootstocks or sometimes the prior woody stems and growing fast duringthe cooler wet seasons, and will die back as the rains vanish come summer again. If conditions stay wet enough though, some plants can persist in green year round. Near the end of the winter season typically though, before they die back, these plants will send up anywhere from one to several dozen stalks that look very similar to the leaves, but are tipped in little oblong buds that swell and part to eventually reveal glossy purple-pink, brilliant blooms that can be nearly two inches across. One is beautiful enough, but with a happy plant sporting dozens, it can be a spectacular sight: a full bush of purple. Rarely, white-flowered forms may also appear.
These flowers require some special care in order to produce new generations though: the anthers are closed along most of their length save for a pore right at the tips, and they're clustered together with the stigma on a skinny stalk curving out and well away from them. This is a situation built for "buzz-pollination," where insects with high-speed wings such as bees or hoverflies must approach and vibrate the anthers in order to shake the pollen out of them, and then fly to a new flower to transfer it. Additionally these much like most rainbow plants are self-incompatible; pollen will not successfully germinate and grow into the stigma of a flower with the same genetics to fertilize the ova, it must be transfered to an entirely different plant that sprouted from a different seed. This forced cross-pollination ensures that genetic diversity is kept higher and that inbreeding is less likely in a particular population, but it also means you have to convince the bees or flies to visit different plants one after the other rather than just more flowers on the same plant. This is likely one reason why the plants produce so many blooms at once.
Once cross-pollination is achieved however, the petals dry up and shrivel away, and a little semi-spherical pod develops over a period of a couple of months. When it dries and turns brown, it splits along a single fracture line and releases a whole bunch of small black seeds that are semi-hydrophobic due to the little protrusions all over them (the exact shape of the seeds and how these protrusions are arranged is another feature that separates it from gigantea, which otherwise looks about identical) and so fairly well dispersed by water. At the time the seeds are usually release though, water is becoming scarce and they will wait dormant through the hot summer. Those seeds need something else to happen before they will germinate come winter again though: fire.
Yes, as so many societies are finally starting to realize again, fire is not only a natural part of many ecosystems, for many thousands of species it is necessary for survival. The seeds of many rainbow plants contain chemical inhibitors that prevent germination, and the natural means by which these inhibitors are removed is by exposure to the chemicals released by burning vegetation, the smoke that results. Western Australia is naturally prone to swift-moving, low-temperature fires during summer, which burn away dead grasses and old branches (such as the stems of adult Byblis) and the resulting ash mixes in with the soil and seeds, soaking them in chemicals once the first rains come by and thus triggering the new seedlings to grow up in an environment that is less choked in potential competion for sunlight and with slightly richer soils for a boost to grow.
This need for fire/smoke exposure might be one thing preventing this species from becoming more popular in cultivation, but it's something easily overcome. My personal preferred means of treating seeds is using gibberellic acid, or GA3 solution, which similarly counteracts the inhibitors and permits germination. 1000 parts per million solution, soaked for 4-6 days, results in germination after a few weeks. However there are other methods too: literally burning grass over the pot of seeds and watering the ash in, or you can even purchase liquid smoke (often used for flavoring meats) and use this to soak them. The seeds should be planted either in transferrable biodegradable pots or the pots they will eventually be permanently established in as they're not huge fans of transplanting (though I have found them to care far less about root disturbance than the annuals do), in a fairly coarse, well-draining mix of sand or similar inert substance, perlite, and a bit of sphagnum peat moss. Once they sprout they should be kept moist and monitored carefully, kept somewhat humid but not overly so as they can be prone to damping off fungus, and grown in very strong light if not full sun. A slow release fertilizer pellet buried and inch or two in the soil is also actually beneficial to these and other rainbow plants, one per plant give or take, and feeding the leaves with liquid fertilizers, small insects, or something like bloodworms or fish flakes helps them grow rapidly and establish.
Adult plants can, as I have found, be kept in fairly small pots, but for the best flower show and healthiest specimens using pots of a gallon volume or larger is best, one plant per pot unless it's a very large pot. Two different clones are needed to pollinate for more seeds, and you can use a tuning fork to gather pollen, or I have found just flicking the anthers with a toothpick will drop pollen as well. You can also propagate these plants via cuttings and establish healthy plants as a result; they will naturally send up smaller offshoots when fully mature as the seasons turn over, or you can cut the main stems, bury them in a moist potting mix, and keep them humid and slightly more protected from the sun until they establish new roots and begin growing. The file for this species as reference can be found here: https://www.carltoncarnivores.com/byblis-lamellata And hopefully this write-up might just encourage others to try out growing these plants; they need a little more care than your average sundew or flytrap, but are worth it once they mature and being showing off their multitude of flowers.