Other options:
Take 1 level of Druid and then cast druid spells from another source (Archivist or Spirit Shaman).
If there's a way to cast druid spells as an arcane spellcaster you could take a dual-progression PrC, I don't think there's a divine/divine one the way there's arcane/divine, arcane/arcane, etc.
As the DM, you get to decide what content is permissible. Make them an Arcane Defiler from Dark Sun. It solves basically all your thematic issues, and there's an ACF to swap your wizard familiar for an animal companion, so you'd still be themed as a druid. Just lose out on wildshape.
Alternatively, an early entry Walker in the Waste Domain Druid can get in at level three. (Uses assorted dragon magazine and unearthed arcana content, and an implied 'Alternative Class Feature equivalency' rule)
Human Domain Druid + Swift Druid ACF
Nature Sense, Wild Empathy, Turn Undead, Fast Movement (Barb), Monk AC + Wis to AC, Favored Enemy, Track feat.
Lose: Spontaneous SNA, Armor/shield proficiencies, Wildshape.
H1: Magical Training
L1: Precocious Apprentice (take Dessicate)
F1: Heat Endurance
F2: ???
D1: Track, Pick two domains, one of which must be the Thirst domain.
F3: Practiced Spellcaster
F6:
F9:
F12:
Such a character would be a Dry Lich, have a massive aura of extreme desert conditions, have almost full druid casting, can create sand golems and salt mummies, and a number of useful SLA's. No wildshape, but sustantial resiliency (by writ of being a lich and not dying when killed).
Given that the desert condition aura is out to 100 ft and defaults to whichever is hotter between local conditions +2 heat steps or extreme heat, you'd get the massive forest wilting effect that you'd see with a Blighter, without the ridiculous need to om nom the forest to cast spells.