When to start watering/blooming now

Jane McGary janemcgary@earthlink.net
Sat, 19 Oct 2013 12:40:31 PDT
I completely agree with Peter Taggart that watering of many 
summer-dormant bulbs should be delayed until soil temperature is 
cool. This would be later with bulbs in pots that are not plunged. I 
also agree with his principle of "damping down pots in very dry 
summer conditions." This is especially important for small seedling 
bulbs in pots. By "damping down" we mean just waving a water wand or 
watering can with a rose over the surface of the soil, not by any 
means soaking the pots. You just want humidity.

On the other hand, there are bulbs from summer-dry areas that inhabit 
moist habitats such as the margins of lakes and streams. These tend 
to make root growth if not top growth while the weather is still dry, 
so they will succeed better if you don't dry them out so much. 
They're also the best adapted to typical garden border conditions. 
You need to look at micro habitats as well as regional weather 
patterns. Examples of bulbs that flourish with summer water are 
Fritillaria meleagris, Narcissus jonquilla, Erythronium revolutum, 
and Crocus speciosus. I think Cyclamen purpurascens may also belong 
in this group.

I'm also noticing that many bulbs I planted in turf are tolerating 
the weekly summer watering they get better than they might in a pot 
or in the bulb house. No doubt the dense grass insulates the soil and 
moderates its temperature. In nature some of the fall bulbs grow well 
in short turf that is grazed earlier in the year. In pots, a fairly 
light-colored stone mulch might have a similar effect, as long as the 
sun doesn't hit the sides of the pots; you would want to put them 
close together if you don't have a way of burying (plunging) them to the rim.

Now most of my bulb collection is in a "Mediterranean house" (solid 
transparent roof, wire mesh sides) in raised beds. It got watered 
this year earlier than I would have chosen because we had unusual, 
torrential rainstorms for several days in September, resulting in 
rain blowing in and groundwater being drawn up through the porous 
barrier below the beds. I don't know whether this harmed anything. 
The weather is clear and mild now and the crocuses are opening 
beautifully both under cover and outdoors. The nights are around 45 
F/7C, and days around 65F/`18 C, so I don't think anything is getting too hot.

Jane McGary
Portland, Oregon, USA

19/2013, you wrote:
>I believe that the important thing is not to water until the weather cools
>down - or at least until the temperatures fluctuate between day and night.
>Hot and wet = rot in many winter growing 'bulbs'. In cool Summers this
>problem may not apply and so watering early will simply start off early
>I do believe in damping down pots in very dry Summer conditions, It is very
>important to remember that this is not the same as wetting the bulbs with
>an autumnal soak.
>Peter (UK)

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