Frugal tomato seedlings

Up here on the rooftop, I have a head start on plants and seedlings because my last frost is earlier than that on the ground. Therefore, I can start my plants earlier. Here is a recent tomato plant that I have grown from seeds from last year's tomatoes: Granted, I have a perfect growing environment here on the roof, over the average UK growing climate....but I must admit--I find seeds to be expensive around here.

A pack of tomato seeds from Asda (aka Walmart) is 1.95 GBP (2.21 EUR/3.19 USD). It then follows that plants are more expensive than seeds. A single tomato plant at homebase (like Lowe's or Home Depot) is 1.98 GBP, which is slightly more than the prices I just listed.

Of course growing your own is cheaper than supermarket prices, no doubt, but starting seed from scrath is ridiculously cheaper than buying new plants.