Yes, you can grow great juicy tomatoes in bags. There are actually to methods of doing this. The first is growing tomatoes in grow bags that you have to add soil to. The second is the European method where you buy large bags of potting soil or compost and plant the tomatoes directly into the bags. Both methods work, and we will talk about each of them.
Let's talk about empty growbags first. The best option is to buy grow bags specifically made for growing tomatoes. Fabric grow bags have the advantage of allowing air to circulate around the roots. Many people just buy plastic trash bags to grow their tomatoes in. If you use plastic bags, get some that are chemical free. Some bags have chemicals in them to fight germs, and these are not good for your tomatoes. Black bags will be hotter than white bags.
Fill the bags 2/3 full with a good organic potting soil. Tomatoes in a bag can dry out easily so get some coir or coco pith from a garden store and add some of this to help retain water. The coco pith will absorb water a release it gradually. Mix in a cup of kelp and a cup of alfalfa meal. The kelp will help plants get minerals the roots would get from the ground if they were planted in an outside garden, and the alfalfa meal will stimulate growth. If you are using plastic garbage bags, poke some small drainage holes in the bottom. You can use a small stick or toothpick; placing the holes about three inches apart.
The best type of tomato to plant in bags is determinate because they are self supporting. With other types, you will need to use stakes or tomato cages for support.
Add water to the bag until the soil has a spongy consistency. If you are planting seeds plant three seeds in the center of each bag. If you are planting seedlings remove the bottom leaves and plant the roots deep in the soil. To give your roots a little support, put some small stones around the stem. The stones will also absorb heat during the day and release it at night.
Growing tomatoes in bags requires consistent watering. You want to keep the soil moist but not wet. If they aren't kept moist, the plants can get blossom end rot. And if they are kept too wet you can kill the plants. Before watering check the soil by pushing your finger in about an inch. If the soil feels dry water the plants.
Growing tomatoes in bags of potting soil.
In the UK people often grow tomatoes in potting soil bags. This method is also often used for growing tomatoes in greenhouses. The plants can even be started in a greenhouse this way and then moved outside before the plants mature.
Buy large bags of potting soil and plant two or three plants in each bag.
They actually make bags of soil specifically for planting tomatoes in them. These are typically about one foot by three feet. Since the bags have probably been sitting for a while, it is best to loosen the soil by flipping and shaking the bags. This will make it easier for the roots to take hold. Make sure the soil is spread evenly and there are no clumps. If there are not already some drainage holes in the bottom make ten to twelve with something sharp like a knife. Now using scissors or a knife make a small cross where you plan to plant each tomato seedling. After you cut the crosses fold the flaps back to make square openings. Keep in mind that the soil will dry out faster with larger openings.
Now make a small hole in the soil and place each seedling in, just as if you were planting them outside. You can also start from seed if you wish. Once the seedlings are planted fill the hole around them and water right away.
After the plants are seven to eight inches tall, they may need some support. Bamboo sticks are often used for this. Just stick the bamboo in the bag and loosely tie the stems to them as the plants grow. Another option is wire grow cages.
