Another topic alot of new vert growers are concerned with is, whether or not they should veg their plants vertically. I see this question asked all the time. I don't believe there is a correct answer, but there are a few factors you should consider when making your decision.
Veg'n your plants vertically will cause them to grow out towards the bulbs and promote strong lateral branching (because the sides are getting blasted with light)
.Most vert vets like to keep the bulbs slightly higher than usual to encourage the plants to still stretch upwards. The plant will also begin to develop a "front" and back" naturally. The front being the side facing the bulb(s). I like to start training the branches in the back to the front and/or clear out the rear foliage. (strain dependent)
These factors may be positives or negatives depending on your overall situation, but you'll be able to take advantage of them or make adjustments if your prepared.
When veg'n horizontally plants tend to reach up for the light, and the lower branches are skinnier and slower to develop than new growth on top. Not a bad thing, it's been working for years. Topping and LST'n will get you plenty of branches if that is what you desire. Keep in mind your horizontally veg'd plant will take a day or two to adjust when it is switched to veg light. The fan leaves and branches will start to turn toward the light. The plant will start to show a front and back and you'll probably start some form of training at that time. Again, not a big deal, just another factor to consider.
In my opinion the most important factor is, what is easiest for you? If you have a dedicated flat veg room, it's probably easiest to go that route. If you only have one room, you can go straight from the cloner, into your vert setup. Everybody's situation is different and there are many methods that work well.
I should have said this before.... Everything I'm posting up in this thread is only meant as suggestions based on my findings as a vertical grower. I'm still very new to this myself and make mistakes daily. Please feel free to point out any inaccuracies, alternate methods, or things I left out. I'm just tryna share the love