How to pass variables of each item through to paypals cart when selecting paypal's 'add to cart' button?

Question

I am developing a website selling gardening products using PHP and SQL. The user searches for a plant, finds the one they want, clicks on it for more details and there they see an option to add to cart. I have signed up to Paypal's business account and used their add to cart button. But currently, when I try it out and click the button, it doesn't do anything. Obviously this is because know variables have been passed about that specific product. What do I need to do in order to get each item into the cart?

Answer 1

@QUESTION:

To impliment a normal POST to pass to standard form, follow this tutorial:
http://www.evoluted.net/thinktank/web-development/paypal-php-integration

@INTEGRATED SOLUTION:

Integrated solutions will allow you to make these transactions without going offsite.
Using this method requires alot more security.