There are lots of insects (by the way, spiders are not insects, they are arachnids) that are harmful to flowers and plants. The offenders include beetles, stink bugs, caterpillars, some ants, weevils, and grasshoppers to name a few. Some of these reprobates suck plant’s juices, leaving holes in leafs, others transmit diseases between plants, like mosaic and bacterial wilts, while insects like grasshoppers and caterpillars chew jagged holes in leaves and tatter the edges; in extreme cases they can wipe out entire gardens (or farm crops). Rather than dowsing your plants and flowers with harsh chemicals, why not employ your friendly neighborhood spider?
Spiders help rid our gardens and homes of these unpleasant petal munchers, feeding on them and not on our plants. Spiders are predatory and will eat pretty much any insect they catch, keeping our plants safe and infestation free. They have no interest in eating your plants, their webs will not harm your plants, and they want nothing to do with you (they don’t attack what they can’t eat unless threatened and they have terrible vision, they can’t even see you unless you’re within approximately one foot of them).
Also, in our opinion, lots of spiders are really cool looking, even pretty! And few things rival the beauty of flowers like a dew covered spider web in the morning.
All this praise for spiders we would like to point out that we are not fans of spider mites. Spider mites are mites, not spiders and are bad news for your plants, especially the two-spotted spider mite. They feed on plants, draining their juices, causing major damage and may even kill your plant. They are very small and can be carried by a light breeze, spreading easily from plant to plant, potentially decimating all the plants in your home, greenhouse, or garden. If you have spider mites you should isolate the affected plant as soon as possible. We found many good spider mite control methods here, at How to Get Rid of Stuff.
Not sold on spiders? If it eases your mind, only ~200 of the ~40,000 species of spiders actually have a bite that can cause health problems to humans… so chances are that the spider you save will be of the helpful variety, keeping your flowers and plants happy and healthy and causing you no harm. To save a spider capture it under a glass, slide a piece of paper over the opening and release your new friend outside in your garden. Happy Save A Spider Day!