How much time do I have to improve my lack of extracurriculars before applying to college?

Answered

College applications typically open during the summer before your senior year and are due during December of your senior year (at least for the schools I've looked at), so...

So depending on the college you want to attend you could ignore ECs entirely. For example University if Iowa only considers academics in admission. If you are top10% in your class in Texas you have auto admittence to most if not all public schools in Texas.

And then some schools that do consider them selves holistic may decide your academics outweigh any lack of ECs.

However if you’re aiming for more selective schools assuming you’re a rising junior you should deepen your involvement in at least 3 ECs or have 5-7 total what ever you prefer. Then in senior year try tuning for leadership positions but this year show yourself to be a leader and volunteer so you can be designated as project lead etc so it helps back your resume when you run next year.

Hope this helps and feel free to comment if you’s like clarification as I’d be more than happy to help!

There isn’t a specific amount of time you need, the more the better! I would recommend finalizing a plan this summer and getting started in September when you start your junior year!