EAT YOUR VEGETABLES: Joannah Hill and Carrie Lyle post on vegetable gardening each Tuesday. 

A self-watering vegetable garden for $189. A pot of alyssum for $20. One gardener who crunched the numbers even wrote a book about the average cost of one tomato from his garden: $64.

Gardening can be expensive. But it doesn't have to be.

Some of our favorite cost-cutting tips are listed here. We'd also like to know how you save money in the garden or if you have a favorite source of free compost or bamboo. 

We will choose a comment at random from today's posts and send you a nifty Kitchen Garden Box of tips, recipes and seed storing envelopes from Mike McGrath of NPR's You Bet Your Garden. Just provide your e-mail so we can contact you for a mailing address. (Don't worry, we won't share it with anyone else.)

GENERAL TIPS
* Think small and be patient. Seeds are cheaper than seedlings, immature plants cheaper than mature.
* Don't bite off more than you can chew. If you plan a garden too big to handle, you may get overwhelmed. Better to concentrate on a small plot or a few containers to get the most bang for your buck.
* Do a cost/benefit analysis when deciding what to plant. Basil is $3 at the store but one plant at home provides fresh basil all summer long. For things like shell beans, which don't cost much, you may be better off just buying at the store.

TOOLS AND CONTAINERS
* Look for gardening supplies at a discount at the end of the season.
* Check garage sales for used gardening tools and plant pots.

PEST CONTROL
* You don't need expensive store-bought chemicals to control pests — try homemade solutions, like a teaspoon of dish soap mixed with a quart of water to kill aphids.

SEEDS
* Save seeds from the vegetables and flowers you grow this year.
* Share seed packets with friends. It's unlikely you'll use up a 50-seed packet of zucchini in three years, anyway.

PLANTS
* Get cuttings and plant divisions from friends. No need to pay for daylily, hosta, iris or cannas.
* Check the clearance table at big-box home-improvement stores. We've found roses, clematis and flowering quince for as little as $1. But choose carefully — break a branch to see if it's still green inside, or pull the plant out of the pot to make sure its roots are healthy — and be prepared to give it some TLC. 
* Many garden centers sell plants for up to 50 percent off in the fall.
* Check out plant fairs and local farmers' markets for inexpensive vegetable seedlings.

MULCH AND COMPOST
* Free mulch is available to Baltimore County residents at the Eastern Sanitary Landfill in White Marsh.
* Check with local horse stables to see if you can have free manure. You'll have to do the shoveling, and you might need to age it yourself.
* Check Craigslist or Freecycle for free you-haul-it mulch and compost.
* Compost your own food/yard waste. You don't have to have a bin unless you're composting food and are concerned about rodents. A pile somewhere inconspicuous works fine for yard waste.

Photo credit: iStockphoto