I don't think I'd expect the Eucomis above ground until May or even June. The flowers will be later - July, August, September. They have a long flowering time. They should be fine with temps 14-20C and 8-10 hours of light.

They're fairly drought hardy, yet do appreciate having a good, deep drink. Drooping leaves is indication enough, though the leaves tend to drape later in the season.

About the offsets: you may have to cut them off at this stage, yet it's just as easy to let them grow on with the mother bulb. It certainly doesn't harm the flowering performance.

In the ground they form a slowly increasing clump with the bulbs showing above ground. After the first frosts the leaves turn horridly slimy and drape all over the bulbs and the surrounding ground to give insulation.

If you want more Eucomis then you could try leaf cuttings over the summer, as well as offsets later on.

Be prepared to pot on your bulbs - even this season. The leaves are often 40cm+ and the flower stems at least as high. Wider rather than deeper and your JI3 would give them a good start in the pot - plus excellent drainage. It also lets them increase to a more spectacular clump.

Unless you are in a flat with no garden, they will probably be fine outdoors against a south or west wall.

When you have enough bulbs to spare, you could try over-wintering. They certainly survive 5+ degrees of frost for me, and came through our extremely rare snowfall of a few years back without any check whatsoever. (Still dormant. They might not have appreciated the same thing a couple of months later, though.)

thank you so much for the reply!

I planted them in a 25cm pot (same down) with perlite and mixed in JI3 and bulb fiber was watered when potted and they are now showing signs of growth a small spike and the Heymenocallis has grown about half inch.

I will leave the offsets till they grow a plant then after I will "pick" them

but thank you and how would I rest period them?

Mine get ignored outdoors - frost and rain throughout winter. In pots, however, I'd be far less cavalier.

If your pots aren't frost-hardy - bring them in and keep almost dry then repot February. Not dust dry, though. And above freezing if possible.

You'll probably notice that the lower reaches of a large pot will hold moisture for several months over winter. It might not be readily available to the plants, yet it does keep the bulbs from dangerously drying out.

thank you for the advice :) mine have just started sprout and I only buy (plastic and actually) frost proof terracotta pots.

thank you

Leave the offsets on.
As far as rest period goes, put them under cover a good month before frosts and stop watering. Here in Oxford I reckon early October.
Leaf cuttings are a good way to propagate, the only trick being keeping them moist enough without rotting them. I leave it late. Probably no quicker to blooms than seed, so I would only recommend the bother with cultivars (ie; Sparkling Burgundy etc) and just use seed for the species.

Hymenocallis are easy. Ordinary MPC with plenty of grit for drainage. Water well once in growth. Plant them with about 25/35% of the bulb above the soil line. Use a pot that is MORE than big enough. They multiply rapidly but loath having the roots disturbed, so it's better that they grow into the pot than need repotting/dividing. It's unusual to get flowering sized bulbs in the UK (but they are out there), so don't be disappointed if they don't bloom this year.