Can I grow lithops from seed in the UK winter?

Question

I just bought some lithops seed that I'd like to plant indoors in London, UK. Is this at all possible?

Do I need artificial light? Do I need a heated propagator?

Answer 1

In the wild, lithops flower in winter or spring. The seeds remain attached to the dead flowers on the plant during the hot dry summer (which is the plant's dormant season) and are knocked out of the flowers at the start of the rainy season in autumn.

Since the seeds float on water, water runoff from heavy rain storms can carry the seeds away from the parent plant. They then germinate quickly and the seedlings grow through the winter.

So, they don't need high light levels to germinate, but they do need reasonably warm temperatures, about 65-80F (18-25C).

A way to simulate the natural germination conditions is to thoroughly water the compost, then cover it with a thin layer of fine grit, then spread the seeds (which are tiny) mixed with fine sand so the mixture falls into the cracks between the grains of the grit.

To avoid washing the seeds about while they are germinating (since they float on water), water using only a spray bottle, and cover the seed tray with a sheet of glass to maintain humidity.

In the right conditions they should germinate within 2 or 3 weeks. The rate of growth after germination depends on the species - some grow very slowly compared with others and may only produce plants 1mm in diameter in the first growing season.

Probably the ideal time to start them would have been in August or September, but if you have bought seed from flowers produced in winter 2019/2020, keeping it till next year might reduce the germination rate.