Hello lily lovers,
I'm from the Czech Republic (central Europe) and I have constant problems with the care of oriental seedlings. I know that orientals are hypogeic and form a bulb underground in the first year. But since I didn't know how to take care of and how to water the bulbs that I can't see underground, I followed instructions from some article that I once read. It said that the time between sowing and the first flowering of orientals can be shorten by one year. According to the instructions, I sowed the seeds in a transparent plastic bag with perlite, which I continuously moistened, folding the top of the bag over to keep the moisture inside. I don't remember when I sowed, but the first leaves appeared in the summer (a year after I harvested the seed pods). The bag of perlite and seeds was placed by the window so that it was constantly in contact with light, the sprouted bulbs soon turned green and then released leaves. So, as soon as the leaves appeared, I transplanted the leafy bulbs into a pot with substrate (a mix of clay and substrate for geraniums in a ratio of 3:6 - several asian seedlings have already bloomed when growing in this mix). During the summer, the seedlings in the pot produced several new leaves. I put the pot in the cellar for the winter. About a third of the seedlings survived until spring, but throughout the spring and summer they grew larger leaves than the previous year. Unfortunately, they didn't want to stop making new leaves in the fall, and even with the onset of frost, they kept growing new leaves, so I put them in the basement and stopped watering. A single seedling survived the following winter, which grew a low stalk in the spring, but died during the summer.

I know that oriental hybrids are difficult to care for and many people here on the forum do not cross them, but I would still be grateful for any advice, especially regarding the composition of the substrate. So far I'm thinking about mixing river sand, geranium substrate, peat and clay. Naturally, the substrate will not contain calcium.

I am attaching several photos of oriental seedlings from previous years.

Thanks so much for your detailed explanation (and excellent photos!). It helps us give you better answers. For a beginner with oriental seeds, you have done really well, as they are more difficult than asiatic lilies.

I see two things that might help you.

1. Remember how beautiful and healthy your seedlings looked inside the bag with the perlite? They had adequate moisture AND adequate oxygen from the large air spaces provided by the perlite. When you put them in a mix with clay, those large air spaces disappeared and became very small because the size of the clay particles are miniscule, and fill up all the air spaces in the soil. This also encourages water to fill up any remaining air space and exclude oxygen that the roots need to thrive.

Orientals are more vulnerable to this problem than asiatic lilies. I think you need to use much less clay. I would use 1 part clay and 10 parts your geranium mix.

2. Asiatic lilies are more tolerant of acid OR alkaline soils, but Oriental lilies like acid soils. Your clay in the Czech Republic is likely derived from the limestone bedrock and is neutral or alkaline pH (not acid).

We as humans can survive on junk food, but it's not good for us, and it causes problems later on, like getting fat or other health issues. Same with plants. Although oriental lilies can survive in neutral or alkaline soils for a while, it's not healthy for them and they are more susceptible to problems like bulb rot.

Oriental lilies in particular are more susceptible to bulb rot in winter than other lilies, and I think this is the what is happening to you. A healthier bulb (more air spaces in the soil and an acid soil) will enable better success.

Lwftwood, thank you for your advice. You're right, when I look in the pots with adult orientals now, despite adding the geranium mix, the soil is still too clay-like and not aerated. So I will dramatically reduce the amount of clay for next season, add more of geranium substrate and also coarser sand.

I have a lot of rodents in my garden, so I was thinking of burying the pots with adult bulbs in the ground for the winter. I would drill a large number of holes in the bottom of each pot to allow water to drain quickly, however I am concerned that the surrounding clay soil will drive water into the pot from below, is this possible?

Lavenders11 said:...however I am concerned that the surrounding clay soil will drive water into the pot from below, is this possible?

You are an astute gardener, Lavenders11. That is what will most likely happen, but not quite in the way you expect. Water can back up inside the pot and flood the soil (and rot the bulb), but the excess water comes from above, rather than from the bottom. Rain or snow water drains freely through the pot soil until it runs into the clay below. But the clay drains slowly, so as more water drains freely through the pot, there is not place for it to go, so it fills up the pot. It's called the (soil) bathtub effect.

Eventually, the water does drain out the bottom of the pot into the clay soil, but your bulb will have already rotted.

Sinking the pot into the soil is a good idea, because of the temperature moderation of the ground. Your bulb will like that. All you need to do is prevent too much water from entering the pot from above. You can do this by putting a larger pot upside-down over the pot sunk in the soil. You still want air circulation inside, so the drain holes that are in the pot already is a good thing and keeps temperature from getting too high when the sun hits it, too. A standard clay or light colored opaque pot works best. And it will keep the rodents out, too!

@Leftwood I'm facing the same issue here this winter....after an horrendous extended summer drought now we are having rain almost every day. So for the time being all my previous year lilies are being repotted into a new grow bags and kept under a waist high polytunnel; however I will eventually run out of space. So I'm planning to sit my grow bags inside a trench outdoors. As an alternative to placing pots underneath the lilies, could a layer of very coarse sand mixed with pebbles, beneath do the trick? My soil is naturally almost pure sand so I haven't seen a bath tub overflowing situation...( nor would I want one for sure). In spite of copious rains, puddles still are draining fast, no standing pools.

Arturo