Mishnayos Challah Perek 3 Mishnah 4

Similarly one who dedicates his produce prior to the stage when they are subject to tithes and then redeemed them, they are liable [to be tithed]. If [he dedicated them] when they had already become subject to tithes and then redeemed them, they are liable [to be tithed]. If he dedicated them before they had ripened, and they became ripe while in the possession of the [Temple] treasurer, and he then redeemed them, they are exempt, since at the time when they would have been liable, they were exempt.

כַּיּוֹצֵא בוֹ, הַמַּקְדִּישׁ פֵּרוֹתָיו עַד שֶׁלֹּא בָאוּ לְעוֹנַת הַמַּעַשְׂרוֹת, וּפְדָאָן, חַיָּבִין. וּמִשֶּׁבָּאוּ לְעוֹנַת הַמַּעַשְׂרוֹת, וּפְדָאָן, חַיָּבִין. הִקְדִּישָׁן עַד שֶׁלֹּא נִגְמְרוּ, וּגְמָרָן הַגִּזְבָּר, וְאַחַר כָּךְ פְּדָאָן, פְּטוּרִין, שֶׁבִּשְׁעַת חוֹבָתָן הָיוּ פְטוּרִין: