We have a number of different templates from which to choose, so that’s a hard question to answer. However, as a general rule, you can plan on 30 characters per line. Of course, there are always exceptions.
For instance, if you would like to include a name which contains a lot of capital ‘M’s, it’s going to take up more space than one full of lower-case ‘i’s. Which is an exaggerated example, of course, but it does demonstrate that not all letters are created equal. At least, not in Helvetica.
Generally, most common names and most botanical names (even those followed by the varieties and cultivars), tend to fit perfectly well within 30 characters. On occasion, that isn’t the case, but luckily the tags and signs are proofed before printing, and font-size can be individually tweaked when necessary.
If the space provided on any line of our tag / sign form isn’t long enough for your text, send us a message and we will work with you to ensure that your tag or sign meets your needs, be it by adding a line or reducing the font-size.