Hi, I'm not sure where you are located. Here in Florida, I have my tomatos in a place that gets about the same amount of direct sunlight. So far, the tomato plants are growing and look good. I have also grown under lights, and while it is OK, my choice would be to try the sunlighted area first, even with reduced direct sunlight. I found 10 gallon tote boxes at wal-mart and other places selling for around $4 dollars each, and have put together some grow boxes using them. I think that 5 gallon pails would work fine, but with the 10 gallon tote boxes, I was able to add an inner liner that holds the potting mix a few inches above the bottom of the tote box. This provides a resivoir space. The idea is to have a self watering grower. I only have to water the plants every 3 to 4 days. The inner liner is made from a good brand of landscape fabric. I guess some landscape fabric is very thin and cheap, but the stuff I am using is tough. The fabric is attached around the top edge of the tote box so that when filled with potting mix (not dirt), the bottom sits in several inches of water. An over-flow hole prevents overfilling, so you just add water until it starts to come out of the over-flow hole that is cut into the tub several inches above the lowest point of the inner fabric liner. The idea came from reviewing construction of homemade earth boxes which have become pretty popular. The commercialy made earthbox growers can cost roughly $35 to $45 dollars or so, and I figured I would need a dozen or so because I live in a retirement park and can not have a regular garden, but can have as many potted plants as I wish. Cost of the grower I buit is about $5 dollars when you add the cost of the liner material. It came in a roll of 3 ft X 50 ft for $10 bucks. A 3ft X 3ft size is plenty for each box, so I have made 7 grow boxes so far, and still have plenty for future use. Well, if you care to take a peek at the grow box I am describing, just follow the link below. Good luck, and let me know if you like the idea. chuck Here is a link that might be useful: An option to using 5 gal buckets

If you live in a hot climate, a shade garden can actually "mature" faster because the plants are protected. But it depends on what you're going for. The way I see it, there are basically 5 kinds of plants/components that make a perennial garden. 1) Long-lived perennials that slowly grow (including hostas) which can take 2-3 years to really look their best. 2) Short-lived perennials or re-seeding annuals that "mature" in 1 year, spread aggressively but are held back by competition in an established garden. 3) Bulbs that are at their peak right after being planted; even if they naturalize, they still look good after 1 year. 4) Spreading groundcovers that fill in gaps. 5) Woody perennials/shrubs. So for the first category - a hosta, as a shade plant, isn't going to take any longer than an ornamental rhubarb or liatris or some deeply-rooted plant that fills out in the third year. Short-lived perennials "mature" just as quickly in the shade but their look will be different; they'll be lighter, more airy, and bloom less heavily, but will still fill in the following summer if you seed in late fall. Bulbs... might actually do better in the shade if your most limiting factor is your hot/dry climate. The right kind of spreading groundcovers will grow more quickly in the shade, IF you plant lots or cut them into small pieces and spread them around to propagate. Ajuga, for example, will look "established" in the 2nd year and if you plant the baby plants 1-2 feet apart, they can easily be completely blanketing the ground after 2 years. Same with lamium, and a lot of other rapid spreaders. Shrubs... do grow slower in the shade.

I qualify for the old and long time (almost 50 years). But I am not a traditional sq ft gardener, though I do use raised beds and the close spacing of intensive gardening. I often recommend sq ft gardening for new gardeners. It is a good way to have some initial success. Adherence to Mel's mix results in a highly permeable medium and the good oxygen diffusion that is paramount to intensive gardening. But the components of Mel's mix do break down with time. Merely adding more does not produce the same as a completely new mix. With success comes the desire to have more and more bed space. And then the complete replacement of Mel's mix becomes very expensive. I think most who expand their gardens will move on to a cheaper way of gardening using the things they have learned with the sq ft method. I myself use a medium of sand and clay with sometimes the addition of vermiculite to achieve the same oxygen diffusion of Mel's mix. It's a permanent medium that doesn't need periodic replacement.

Thailand has a great culture of gardening, I'm surprised you're not looking locally for what is grown there. Being on an island, apart from year round warm temperatures you'd also have very high humidity. Most plants you were accustomed to seeing in the UK wouldn't cope there. But your gardener should be able to indicate what would. I live in a climate which is relatively similar to yours, except not an island and a bit inland, so it gets hotter here and also colder, although rarely anything around 10C. But the biggest problem during the dry season (winter) is the heat and low humidity. That's not a good combination for many plants, although it does mean some summer mediterranean climate veggies we can grow during winter. But I'd say your humidity would prevent that. Good luck with your venture.