Propagation can be carried out in two ways: by vegetative offsets (pups) and by seeds.
Pups should be removed when they are one third to one half the size of the parent plant (taking into consideration the width and height). This will allow the mother to produce more pups. The pup should have a firm, brown base and ‘good form’ before being removed. If it feels ‘soft’, leave it for a bit longer. The first pups produced are always the strongest.
Stoloniferous pups (growing on stems) can be removed with secateurs. For pups closely attached to the mother, use a clean saw edged knife, cutting as close as possible to the mother without damaging her soft tissue. Damage to the trunk of the parent invites bacterial or fungal attack, the same applying to the pup if cut too short. It takes months for a pup to recover from too short a cut or being removed when too little. Some dust the mother and pups with fungicide (no copper). Pups growing from the centre of the mother are more difficult to remove and take practice.
Leave the pups for 24 hours before planting. Many use peat or sand or vermiculite/perlite initially till the offset produces roots before potting on into the usual potting medium. Others plant straight into the normal potting mix and make sure the pup is not too deeply planted yet is stable.
Sometimes it’s necessary to tip the plant out of the pot so you can see what you are doing. Also carefully remove any leaves obstructing the view of the base of the pup.
Give the mother a small amount of controlled release fertiliser and she will probably produce one or two more batches of pups.
The best time to remove pups is in the warmer months – mid October through to March, though some avoid the hottest part of this period. Pups removed in the cooler months will not grow and may rot.
Some bromeliads produce small grass like pups called adventitious pups e.g. Alcantareas. Remove them when they are 10 - 15 cm tall.
Vegetative propagation does not apply to all bromeliads e.g. some species of Tillandsia do not pup at all, but produce lots of seeds to carry on the species.
This is a broad topic and local bromeliad societies and experienced growers are a great source of information. We plan to provide more information on this topic in the near future!