If you want to keep your tulips happy over the summer, don’t irrigate. Ill.: gallery.yopriceville.com & www.aquarion.com & www.sccpre.cat, montage: laidbackgardener.com
Did you know that irrigation systems and spring-flowering bulbs (tulips, hyacinths, crocuses, etc.) don’t always mix? During the summer, when these bulbs are dormant, they don’t need water and can rot if they receive too much. And even if they survive well-watered summers, their ability to bloom diminishes. That’s why you always find the most beautiful perennial tulips in flower beds that aren’t irrigated.
Some botanical tulips, such as T. hageri, T. humilis andT. pulchella (T. humilis pulchella), have even more extreme needs and prefer near-desert conditions: hot summers with almost no rain. And yet, they love cold, snowy winters. Scorching hot, arid summers and cold, snowy winters? That’s not a combination all gardeners can offer! That’s why these xerophytic tulips behave like annuals in so many gardens.
It’s commonly said that botanical tulips tend to be more perennial that other tulips and there is certainly some truth to that, but to make that work, you have to mentally subtract from that equation the arid climate ones like T. hageri, T. humilis and T. pulchella!
If you do use an irrigation system to water your flower beds, that doesn’t mean you have to give up on all spring-flowering bulbs, because there are exceptions: bulbs that don’t mind moist conditions while they’re dormant. Daffodils (narcissus), alliums, camassias, chionodoxas, grape hyacinths, snowflakes, snowdrops and squills are among the bulbs grow well in irrigated flower beds, and often even proliferate there.
Even so, a true aficionado of spring-flowering bulbs would probably do best to keep summer irrigation to a minimum!
I gave up on tulips anyway, just because they are unhappy with our climate. Because our rain stops so early (normally), we would need to water them until dormancy. Also, they need to be dug and chilled. There are easier perennials to grow. Someday, I intend to try at least one of the species tulips.