ZFS question: "L2ARC is disabled"

[Kent Kuriyama]

I have set up a ZFS pool (zpool0) with both zil and L2ARC.  The output of
zpool status is:

------------------------------------
zpool status
  pool: zpool0
 state: ONLINE
  scan: none requested
config:

        NAME        STATE     READ WRITE CKSUM
        zpool0      ONLINE       0     0     0
          da0p2     ONLINE       0     0     0
        logs
          ada0p8    ONLINE       0     0     0
        cache
          ada0p9    ONLINE       0     0     0

errors: No known data errors
----------------------------------

When I run "zfs-stats -v" I get the message "L2ARC is disabled".  ARC is
healthy.  Can someone please tell me what I am doing wrong to prevent L2ARC
from being enabled?  I am running a qbittorrent on a FreeBSD 11.0p3 system
and expected to benefit from L2ARC because of the intense read activity.
Both the ZIL and L2ARC are on an SSD partition.

Thanks,

Kent