I need suggestions for my garden!

Hello,
I just found this forum and loved it! After reading all those threads and seeing the beautiful pictures of your gardens I'm pretty sure you'll be able to help me.
Ok, here's my problem:
I always lived in apartments, so I never really cared about gardening, or buying plants, but two years ago me and my family moved to this house with a big front garden that had nothing in it but weeds (the previous owner left the house empty for a couple of years)! Then I decided I would make a garden out of those empty beds, and started buying and planting stuff here and there(I had no idea how to do that, LOL!). The result was an ugly colorless garden, so I thought I'd wait some time for the plants to fill in. After a few months, when it was looking better we had a frost that killed EVERYTHING but the hydrangeas and azaleas(rhododendrons?).

By that time I got so frustrated that I decided to give up on planting and start to read more about gardening. That was when I learned about the annuals, perennials and hardiness zones. Here in Brazil, like 90% of the country (including where I used to live before moving to my new house) hardly ever gets freezing temperatures, so plants like vincas, petunias, impatiens, portulacas, geraniums, begonias, etc. stay green forever, and people aren't used to the annuals and perennials talk, and neither was I when I planted all those plants around my garden.

Ok, now I've been living here for 2 years and I know what the weather is like throughout the year, also that most annuals will die during our winter. That's why I need some directions on what perennials will thrive and give a cottagey look to my garden!
I want to be sure of what to buy, because, since most of Brazil has a mild climate, the plant industry is more focused on tropicals and annuals (most perennials wouldn't make it in here), and I'm probably going to have a hard time finding them. Actually I'm considering buying seeds online (from other countries), if I have to.

About what zone I'm in, I'm not sure. Summer here is really cool, highs over the 80s are really unnusual. Winter is cold and windy, the average low temperature is 37F, but it can easily get down to 20F during cold fronts. Ground temperature can also get low, because we usually don't have a snow cover. Most of the garden gets 6~8 hours of sun, and I also have a shady spot under a tree.

I already had luck growing lupines and foxgloves from seed, but they get really tall and I don't know what to use as groundcover. Sweet Williams also did very well in here!

Right now it is late fall in here, and I was hoping to buy things fast so I could do some winter sowing ;)

Well, that's it! I hope you can help me..!!
Thanks,
Lara

p.s. When I see all your spring pictures I feel so envy! It's FREEZING in here.. I'm attaching a picure I took yesterday morning. And sorry for any errors in my english!

Hey Lara, welome! I always enjoy hearing from folks from different countries. And don't worry about your English, it's more than fine, and very understandable.

Although the information that you gave is really important, the length of your seasons are, as well. What month is the last month to have freezing temps and when does it start to freeze again? How much rain do you get, and is it all in one season or throughout the year?

One of the best shortcuts to finding out what does best there is to look at your neighbors yards, the local landscaping and even the open fields and meadows. You can always get seeds from other places but nothing will ever do as well as what is native there, unless it does too well and becomes invasive, something no one wants to be responsible for.... invasives can be a huge problem.

As you have seen there are some *very* talented gardeners here, so I'm sure you'll get the information you need.

Welcome, again!

Lara,
Where exactly are you located in Brazil? Brazil is a gigantic country, most of it tropical to sub-tropical. The climate you are describing sounds like you must be pretty far south in Brazil. I have spent a lot of time Brazil myself and I know that there is a very active Dutch community (Hollambra), near Sao Paulo, where they grow a lot of beautiful flowers, bushes, trees, etc., and they probably sell seeds and cuttings. I agree with the other person that responded to your note, the person that advised you to try to find "in-country" sources for plants. Foreign imports can cause problems - they often do here.
Dick