I’m going to be thorough as possible in the event others look at this post later, so forgive any non-applicable points. And it will be long, so again apologies.

1- Clearly establish you are adequately proficient in English (toefl, etc.). If you can’t meet the requirements of the institution, it’s very very likely you won’t gain admission into the program (almost certain). Then make sure you meet the requirements of the program, those may be higher. Part of this has to do with funding and teaching assistantships, and part of it deals with content delivery to you.

2- Gre’s are important, but really it’s specific parts, like the analytical and math. Verbal is important, but you’ll need to demonstrate that you can think critically, and do some basic calculations. Not often, but site engineering and storm water calculations are a thing in school.

3- Strong honest letters. They don’t need to be flowery, but need to speak towards your capacity to complete the program. It’s ok to include weaknesses and setbacks so much as the overall message is that you are capable and committed.

4- Your letter- just be honest. Why landscape, and why that program? This means you’ll need to do some research about the program and the people. Look and courses, and look at who is teaching them using the registrars course listings if they are online. Then read the faculty bios. You’ll get a sense of how the individuals approach their courses, and how the department approaches teaching as a whole (e.g. a multiple people who don’t  demonstrate an ability to teach the assigned content might be a yellow flag). Do avoid flowery prose. Passion is a fruit, not a reason to be enrolled in a program. Do include significant accomplishments that have an impact and demonstrate leadership and/or independent thinking. 

5- Rhino or AutoCAD might be helpful, but being able to draw line work (not sketching) is more valuable. Sketching or illustrative drawing is helpful too, but it’s different. Most importantly, demonstrate that you are trying to think with the drawing instead of just showing us something that could be photographed. Draw how something is assembled (like a rose), experiment with techniques. You can do with software too, along with models and collage and compelling photography. The key part is to show that you are making discoveries. Poke around here and look at the work by 2020 and 2021 projected graduates. Look at the range of thinking that’s going on. You need not produce this quality of work (note the 1st yr drawing material is omitted), but it’s some of the thinking you need to demonstrate.

And I wouldn’t sell you experience short if there’s a strong sense of craft embedded in it.

6- Do your homework. None of this makes any sense if you go through this process thinking all programs are alike, therefore my letter and portfolio will apply across the board. You need think about what interests you (politics, geography, stormwater, horticulture, etc), and the let that decision help you craft everything.

Most of all, good luck.