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From the article posted by The New Guy

Originally Posted by article

Intro

While most discharge lamps e.g. mercury, sodium, or metal halide lamps emit a more or less pronounced line spectrum, the radiation output of xenon is dominated by a smooth continuum

the continuum is centered around the green spectral range (550 nm)

The present development mainly favours other lamp types, like metal halide lamps and fluorescent lamps for commercial lighting purposes


Results

The radiation penetrating the quartz envelope of a xenon lamp shows an almost flat part with little line structure in the visible range and a pronounced line structure in the IR spectrum
The heat resulting from excess IR absorption by biological tissues will lead to rapid destruction. Excess short-wave UV radiation will also be deleterious to living systems.
Xenon lighting, therefore, requires specially tailored filters which, protect living systems from these spectral irradiances.

xenon lamps should be ideally driven by direct current. This mode, however, results in a reduced lifetime as compared to AC driven xenon lamps.

Metal halide lamps have with regard to the luminous efficiency an advantage of a factor 4 as compared to long arc xenon lamps. This also holds approximately for the PAR region. The main reason is the strong excess IR of xenon radiation.
However, it must be considered that metal halide lighting requires several additional measures, These additional measures reduce the advantage to a factor 2 to 3.

As the IR output of metal halide lamps is much lower, an effective heat control can be achieved by economic glass or water filters. Xenon lamps require more sophisticated and expensive systems of optical filters and cooling techniques to remove the strong excess IR energy.

Despite the relatively low lighting efficiency xenon arcs reach highest artificial luminance concentrated to a single lamp and compare in this respect best with sunlight. Therefore, xenon lamps are unique, for instance, as a light source of projectors and monochromator systems. Furthermore, xenon lamps do practically not need a warming-up time but the full illuminance is available immediately.

The advantage of metal halide lamps is their economical adaptability to biological applications, while xenon lamps provide an almost constant smooth spectral output close to sunlight over a wide range of power.


Conclusion

Therefore , despite considerable competition by other lighting techniques, xenon lamps provide a very useful tool for special purposes. In plant lighting however, they seem to play a less important role as other lamp and lighting developments can meet these particular requirements at lower costs.