I love buying flower and vegetable starts for my garden, as well as starting my own plants by seeds. There are some vegetables you should avoid buying as starts, however, because they are likely to cost you more money than planting from seed and the likelihood of a successful transplant is low. These vegetables are root vegetables:
**Onions do great as transplants!
Here's Why Not to Buy:
1. Transplant Failure
Root vegetables do not transplant well. I am sure if you buy a big pot of root veggies to transplant some will grow and thrive but most won't. These root veggies do not like their roots to be disturbed at all and generally die shortly after transplant because their roots can't handle the shock from transplant.
The other reason root veggies are better planted from seeds is because it is so much cheaper. A pack of seeds is anywhere from a dollar (99 Cent Store, Dollar Tree etc.) to five bucks for the higher end organic seeds. If you buy a pack of seeds there is generally hundreds of seeds in the packet (depending on the variety etc.). If you buy root veggie starts from a big box store you are likely to get 10 to 20 plants in a pot (so 20 radishes or carrots etc.), if you are lucky. The minimum cost is going to be around five bucks for those starts and I have seen them up to 20 dollars! That's 25 cents to a dollar per vegetable. You will get so much more bang for your buck to just plant seeds.
Also, lettuce and greens (mustard, spinach, arugula, lettuce etc.) are much cheaper to buy from seed and super easy to grow. Their seeds packs usually have TONS of seeds too. They generally transplant just fine though if you do prefer to buy them.
So if you are on the looking to grow root vegetables in your garden, consider starting them from seed to save yourself some money.
BONUS: Most of these root veggies are cold hardy and can still be planted NOW! Be sure to check your seed packets to find out for sure.