Seed sowing is great fun, and if you have not tried it then you should. However, not all of us have the time or facilities in which case buying "ready-made" seedlings is a sensible way to go. You get the number you need of the best quality plants delivered to you at exactly the right time to plant. Germinating seeds takes space and if you want a range of specific varieties you will need to buy multiple packets so in reality there is little saving.
The better the seed, the better the plant.You cannot produce a high-quality seedling using old or substandard seeds, so these plants are grown from the best seed money can buy. So that part of choosing good plants is done already. The next requirement is good quality compost - ours is also peat-free. Add the right container; cells for shallow rooted plants and plugs or rootrainers for those with deeper roots and put all three into a controlled growing environment and all the ingredients for perfect plants are in place. Where appropriate, we always harden off our seedlings and we grow them hard - so temperatures are at the low end of the range in which they do well. It makes for stronger plants and if you select nothing else - choose strong seedlings. You will be well rewarded.
Growing Sweet Peas