There were reortedly two explosions at the centre. Workers rescued animals until Lincolnshire Fire & Rescue arrived.
The garden centre is closed during the coronavirus lockdown but essential supplies. It's Fine Foods section is open from Monday 6 April, with food, groceries, essential pet supplies, Seacroft mobility and some limited garden supplies including compost available.
Johnsons said: "Please support us, we are part of your community, but remember, only come for your essential supplies.
"Huge thank you from all the staff for your overwhelming messages of support today."