The first time I ever tried to get rid of snails, well, I was young and idealistic and didn't want to cause pain to any creature, so I gathered them up in a garbage bag and took it to a local park at night. I set the bag down on the grass, opened it a bit and took off. However, one backward look gave me a horrifying sight: a homeless lady was eagerly going to retreive the bag, perhaps hoping for a nice dinner.

One of the low-growing Sedums/stonecrops might be good for this purpose. It is fairly slug-resistant. Many types will be fine in your clay soil fill, and many will do well in afternoon sun. Gold Moss sedum (Sedum acre "Aureum") might work well for you as it is very low-growing and will tolerate moderate foot traffic and full sun. Likes a dry soil, and likely will be evergreen for you in Zone 7. We have Wild stonecrop (Sedum ternatum), which is a U.S. native in our rocky areas, but this stonecrop does better with some shade. Some sedums can get slippery if stepped on directly if they are tall/long, so if you go with a sedum, be sure that it's a very compact, low-growing one that will not send out long shoots over the pavers. See the link below for a fabulous sedum/stonecrop general website that has photos of many, many varieties of sedum. It's the one plant I can think of right now that is slug-resistant, tolerates afternoon sun and clay soil, is low-growing, foot-traffic tolerant, and disease and pest resistant. You wouldn't have to water it excessively so that's always a plus too. Here is a link that might be useful: Sedum Photo gallery

....The idea is to spray the slugs and snails,not the plants... I don't quite understand how that would work in a garden full of plants. Are you saying the ammonia actually has to touch the creature directly? Slugs and snails don't hang around in open spaces, they are in amongst the vegetation. If I can actually see them to spray them I might as well just pick them up and squash them. I garden in a climate where rain is possible at any time in any season so it would not be effective for more than a few hours. It's not a remedy I've ever come across as practicable in a wet climate. I just Googled it and didn't find a single reference to it from the UK. So presumably it only works in certain climates and under certain conditions.

Yeah, I'm not sure why it's been growing so slowly. It's been slow and steady though, and may have picked up lately. As of today, I would guess the volume is about half of that of a hen's egg. When it first bloomed, though, I wasn't even sure it was pollinated because it was growing so incredibly slowly. I wouldn't call our climate heat-deprived--were not at all like SF or Oakland/Berkeley. Our average high in the summer is something like 80 or 82 (we don't have a good nearby weather station). Last summer there were 5 periods (1 or more days) when the temperature topped 95 F. Over the time since the 'Frederick' bloomed, temps have been all over the place--60s, 70s and 80s. Today is forecast for 83. Cool compared to Sacramento or Stockton, but not to SF. I'll try to post in a week or two whether my fruit appears to be headed towards standard 'Frederick' size. You got me for a minute on Tecoma stans--I had never heard about it, so I looked it up. At first I worried that for the longest time I had been calling them Tabebuias instead of their correct names! I checked a picture--very similar flowers. But Tabebuias are in fact trees, and Tecoma is a bush. Moreover, they used to be classified in the same genus. So I don't feel as ignorant, but it just reminds me how little I know (especially about trees). The reason the carpenter bees visited our yard so much this year was because I was growing giant pumpkins (they make a LOT of pollen). The giant pumpkins were in the way of where 'Frederick' will go.