# Want to switch light back to 18 hours, plants are flowering

**URL:** <https://ilgmforum.com/t/want-to-switch-light-back-to-18-hours-plants-are-flowering/82985>\
**Category:** Flowering\
**Created:** [February 18, 2022, 11:01am UTC](https://ilgmforum.com/t/want-to-switch-light-back-to-18-hours-plants-are-flowering/82985 "2022-02-18T11:01:56Z")\
**Posts on this page:** 6\
**Page:** 1

<div class="post-metadata">

**Author:** ![ILGM.Support](https://sea2.discourse-cdn.com/growingmarijuana/user_avatar/ilgmforum.com/ilgm.support/32/260019_2.png) [@ILGM.Support](https://ilgmforum.com/u/ILGM.Support)\
**Post date:** [February 18, 2022, 11:01am UTC](https://ilgmforum.com/t/want-to-switch-light-back-to-18-hours-plants-are-flowering/82985/1 "2022-02-18T11:01:56Z")

</div>

From a fellow grower: I have a plant about six weeks into flowering…probably 3 to 4 weeks from harvest. I’ve started seedlings and want to switch the lights back to 18 hours. Will that affect the flowering plant?

---

<div class="post-metadata">

**Author:** ![MidwestGuy](https://sea2.discourse-cdn.com/growingmarijuana/user_avatar/ilgmforum.com/midwestguy/32/914277_2.png) [@MidwestGuy](https://ilgmforum.com/u/MidwestGuy)\
**Post date:** [February 18, 2022, 11:07am UTC](https://ilgmforum.com/t/want-to-switch-light-back-to-18-hours-plants-are-flowering/82985/2 "2022-02-18T11:07:15Z")

</div>

Yes, unless it is an auto. Autos don’t care about the light cycle. The plant will attempt to go back to veg and will cease maturing the flowers if it is a photo plant.

---

<div class="post-metadata">

**Author:** ![kellydans](https://sea2.discourse-cdn.com/growingmarijuana/user_avatar/ilgmforum.com/kellydans/32/580751_2.png) [@kellydans](https://ilgmforum.com/u/kellydans)\
**Post date:** [February 18, 2022, 11:43am UTC](https://ilgmforum.com/t/want-to-switch-light-back-to-18-hours-plants-are-flowering/82985/3 "2022-02-18T11:43:02Z")

</div>

I suggest start your seedlings in another space. An leave light Schedule on 12/12 . @MidwestGuy Has you covered.

---

<div class="post-metadata">

**Author:** ![oldmarine](https://sea2.discourse-cdn.com/growingmarijuana/user_avatar/ilgmforum.com/oldmarine/32/524771_2.png) [@oldmarine](https://ilgmforum.com/u/oldmarine)\
**Post date:** [February 18, 2022, 2:23pm UTC](https://ilgmforum.com/t/want-to-switch-light-back-to-18-hours-plants-are-flowering/82985/4 "2022-02-18T14:23:36Z")

</div>

> [@ILGM.Support](#):
>
> Will that affect the flowering plant?

Yes it will. Your plant could reveg or even hermie. The plant wants to reproduce. Keep your seedlings in a different area…

---

<div class="post-metadata">

**Author:** ![Deepsix](https://sea2.discourse-cdn.com/growingmarijuana/user_avatar/ilgmforum.com/deepsix/32/855169_2.png) [@Deepsix](https://ilgmforum.com/u/Deepsix)\
**Post date:** [February 18, 2022, 7:13pm UTC](https://ilgmforum.com/t/want-to-switch-light-back-to-18-hours-plants-are-flowering/82985/5 "2022-02-18T19:13:13Z")

</div>

Welcome to the community. Like the others said I have seedlings growing right now in a spare room under a 2ft T-5HO florescent light until I can move them on Sunday.

---

<div class="post-metadata">

**Author:** ![dbrn32](https://sea2.discourse-cdn.com/growingmarijuana/user_avatar/ilgmforum.com/dbrn32/32/533801_2.png) [@dbrn32](https://ilgmforum.com/u/dbrn32)\
**Post date:** [February 20, 2022, 5:09am UTC](https://ilgmforum.com/t/want-to-switch-light-back-to-18-hours-plants-are-flowering/82985/6 "2022-02-20T05:09:27Z")

</div>

Wait a couple weeks and start seeds on 12/12 with the flowering plant. The plants started from seed won’t be mature enough to flower, as long as you harvest within a couple weeks then you can switch light to 18 hours and the young plants will never know the difference.