Leucospermum

Grevillea longistyla X johnsonii 'Long John'. See also: http://hustlepix.com/flowers/ucsc_arboretum_1997/033197-2-10a.html

Protea ????

Protea specie ????

This could be the fruitdetting of the Callistemon

Is in any case out of the Family of the Bignoniaceae and could be a member of the genus Tecomaria

Callistemon rigidus

Euphorbia millii

Agave ferox???

Echeveria specie??

Pleospilos bulosii

Aloe plicatilis

Sedum specie??

In my oppinion a representative out of the Family of the Mesembryanthemum

Flowers of a specie out of the genus Aeonium with in the middle a flower of the Escholtzia californica

could be species of the genus Echinopsis????

Echinocactus grusonii with damaged apex and forming offsets half hight of the body

Mammillaria (spinosissima???)

Aloe ferox

Agave americana