Question
I live in a condo outside D.C.  Love a garden and have had one but can't do it here.  I have Roma and Juliet Tomato plants in pots that will get sun 6 hours a day.  I put two plants in one big pot.  Is this ok? and do I need to give them something extra for being in a pot.  Also I have Arugala in a pot too.  Love this lettuce had to plant it.  How can I make it grow strong and thick?  

thank you
Kelly

Answer
Kelly, tomatoes need one foot spacing between them in order to produce a good crop, so I would definitely plant only one plant per pot.

The three things to keep in mind when gardening with containers is size, materials, and drainage.
Before we get into materials, make sure you are using a good soil mix composed of organic materials such as compost, aged manure, and peat moss.You can purchase 40 lb. bags of these at most garden centers.  Organic matter provides the proper drainage and fertility needed for growing vegetables.

As with any container or basket, drainage holes are essential to prevent drenching the soil and subsequent root rot.  It also ensures leaching of salts from the soil and excess nitrogen buildup.

Secondly, choose a size based on the types of plants you plan on growing, as well as the available space in your planting location.  Too small of a container can result in rootbound plants which tend to dry out more quickly.  I personally believe bigger is better when planting in containers, and would not recommend anything smaller than 2?wide by 18?deep.

I know you specified tomatoes, but you also mentioned a desire to grow fresh vegetables.  Since your primary consideration must be the kind of plants you抮e growing, consider spacing requirements between plants and root length.  Plants such as lettuce have very shallow rooting, while tomatoes require more depth due to their longer roots.  When considering spacing, keep in mind that lettuce needs only 6?between plants while tomatoes, peppers, and broccoli need 12-18 inches between plants.  So unless you have a container with a larger diameter than 2 feet, you will be limited to one container per plant.  The same holds true for vining plants such as cucumbers.  An obvious solution would be to purchase bush varieties that tend to take up less space.  On the plus side, lettuce and snap beans can be planted as close as six inches apart making them much better candidates for containers.

Finally, you need to choose a material that is both attractive and practical.  Alternatives include wood, plastic, concrete, and clay.  My personal preference is rot-resistant woods such as cedar.  They tend to be sturdier than plastic or clay, and moderately priced.  They often come in various colors to fit most preferences.  From a practical standpoint, they also protect the plants better against climate and temperature changes than the other types will.
There are many general purpose books on the market which serve a good references.  My favorite is 揝quare Foot Gardening?by Mel Bartholomew. Although he does have a section on container gardening, it is an all purpose book with a primary focus on intensive planting methods. Rodale has many books available.  I have also seen books at Waldenbooks and Barnes and Noble on this subject.  You can look up any of these companies on the web and do a search to find what you are looking for.

For your convenience, I am attaching a great website with good tips and basic information on container gardening that I抦 sure will benefit you.

http://www.gardenguides.com/TipsandTechniques/container.htm

I hope this answered your question.  Please let me know if I can be of further assistance.

Regards,

Mike