[HeyPK]

I don't think they need resting time. I had one plant going for 5 years without any resting time. Just weigh the rhizome with a stone on some gravel with a small amount of soil beneath, less than a quarter inch. The rhizome should be on top of the gravel, not buried in it. Have some other rooted plants near the bulb, since the lace plant seems to benefit from nearby roots. These plants should not be the kind that grow taller than the lace plant's leaves. Every lace plant I have had started growing right away, unless the rhizome was completely dead to start with. They tended to go down hill later until I found that rather low organic matter soil and companion plants were necessary for their continued health.