I rcently read that house or patio semi-transparent stain for wood can be used on concrete. I know that there is stain made just for concrete, but house or patio stain costs about half what concrete stain is priced at. Does anyone know if this works, or am I better off paying the big price for concete stain?(My old ugly gray patio needs some help! )Thanks!

Interior/Exterior stains will work on concrete provided the is not a build up sealer on the concrete. It will however be prone to fading in direct lights and will not retain as much color as a concrete dye. You will also have to seal the interior exterior stain to prevent the color from being washed off. They look good in the short term, but in the long run, spend the money and use a concrete dye!


Maybe consider giving it an aged look would work using the stain but not full strength.
"Been-There-Forever-Look"
Aging concrete sidewalks/patios
"Clean well, Mix terra cotta colored water base concrete stain 50/50 with water. Paint on with brush on the sides and a roller in the middle. Then use a second, darker terra cotta sopped on a rag and dribble and drip then rub with the rag unevenly.
As with all faux finishes, do a practice piece first."

I also have the directions from another site. Unfortunately it's no longer posted at that site. From Planethorticulture.com
INSTANT RUINS
HOW TO TREAT CONCRETE WITH IRON SULFATE TO GET THAT RUST LOOK
Iron sulfate is useful in staining concrete a pleasant rust or ochre-colored hue, establishing an old look that is potentially very attractive in a garden. The successful application of this technique is dependent on the following factors:
* composition of the concrete surface,
* intensity of iron sulfate applied,
* method of application,
* time it takes the iron sulfate to dry on the treated surface, and
* post treatment completion.
Each of these factors are discussed below. The final project results will differ significantly based on the variation in any of these factors. In addition, please read the warning notice below about the dangers associated with this technique. Consequently, there is an obvious need to have an expert consultation with Planet Horticulture before deciding on this technique, as well as engaging us to perform the renovation project.
Composition Of The Concrete Surface
Materials. Freshly broken, or porous concrete accepts stain the best. Old/weathered, smooth, or finely polished surfaces absorb very little - and probably the original mix will influence the result, all concrete is not equal! Concrete made of various stones, bricks, etc. will produce very interesting stain patterns, since each component will accept or reject the stain differently. This produces a very naturalistic coloration pattern, often fooling people into thinking it is stone. Etched or chiseled patterns, etc. in smooth-surfaced concrete will absorb the stain more deeply than the surface, creating a nice bi-tone effect.
Intensity of Iron Sulfate Applied
Typically, the heavier the iron sulfate is applied, the stronger the color. For the most intense rust color apply the powder heavily upon moistened or wet concrete surfaces, or make a thick paste or slurry and sponge on heavily. In both cases mist lightly afterward to dissolve the powder (this is crucial) or to spread the paste more evenly. If this is an established construction with plants growing in the crevices, the sponge-on technique is the safest for the plants, though some damage is inevitable. The paste or slurry technique is also the easiest on vertical surfaces, especially if there are plants on or near the treated face.
Method of Application
As stated above, the iron sulfate powder can be sprinkled on, or sponged on. If you desire a paler tint, try sprinkling less, or diluting the paste. Or simply mist longer after the initial application to thin (i.e. wash off) some of the applied iron sulfate. Other methods include soaking pieces in a bucket of water into which you pour iron sulfate (ca. 1 cup/5 gal. works well), though the tinting tends to be more uniform (less natural) and not as intense in color. You can also use a watering can to apply a thin solution of about 1/4 cup iron sulfate per 2 gallons water. Mix well and then pour it over the concrete. This will produce a very mild tint, almost unnoticeable. However, this tends to be safe for established plants and can be repeated as many times as you like to develop deeper and deeper coloration. The soft tints are nice when you don't want orange, but don't like the harshness of gray concrete. As you can imagine, this technique can be varied in numerous ways. Experiment.
Time For Iron Sulfate To Dry
The longer it takes for the iron sulfate to dry (after misting), the deeper and richer the color. Thus for deep tints, doing the treatment in the evening, especially during the winter, produces the best rust color. If done during the day in the open, repeated moistening will be necessary for the richest coloration. For best effects in almost all cases, covering with a tarp after misting keeps the concrete moist enough for excellent coloration, though on hot days, an occasional misting under the tarp will help. For full effect, the iron sulfate typically needs 3 to 5 hours to stain. Interrupting this by washing it off earlier, may be useful to get a lighter color, but I have not tried this. Repeating treatments can produce deeper effects if you are disappointed with the first color, but there is a limit to what any particular surface will accept.
Post Treatment Completion
Approximately 18-24 hours after the concrete is stained, wash off the surfaces thoroughly with plain water. This will remove any non-rusted residual iron sulfate. Alternatively, you can mist again and hope the color will intensify. Again, when you are satisfied with the color, wash thoroughly with plain water so any residue not only gets off the concrete, but is thoroughly leached into the soil, especially if you intend to establish plants in the adjacent soil. For flat surfaces, such as a patio or walk, it is easiest to stain the concrete first, then insert surface plants a week or so after. This avoids the toxic effect on your planting.
The iron sulfate stain is permanent, though initially some color might come off so avoid contact with clothing for a few weeks until normal watering or rain has had a chance to remove this loose coloration. If the treated surface is scratched or chipped, spot re-treatment might be necessary, as the stain is typically very shallow.
Although the coloration is permanent, aging may soften the color effect. As with any slightly porous surface, algae, lichen and even moss may establish themselves on the concrete, or calcium salts may leach out. In most cases, this will enhance the appearance of age and naturalness. This can be speeded up by watering frequently with dilute fertilizer, but it will obscure the orange coloration with time. If the effect must be rust or bust, annual re-application may be necessary, especially in moist shaded sites.
Happy Staining!
Advisory: Iron sulfate (sold in many nurseries as a white powder used to acidify soil) will damage, or even kill, many plants that it comes in contact with. Damage usually occurs only on those plant parts that actually get the iron sulfate on them. The action is not systemic. However, a plant may die if enough material gets on the plant crown. Young, tender, new growth, or recently-planted plants are the most susceptible to damage. Further, iron sulfate can stain more than concrete, including your hands or your clothing. Wear latex gloves and a long-sleeved junk shirt (and pants) and rubber boots or shoes. You will find that it gets on more than you intended, since it is a dusty powder.