Yes, adding vinegar will boost the solubility.
I looked there last night too and I still can not see anything on strontium hydroxide. I still can not find it. Do I need new glasses
It is implied by this statement, although it may also relate to strontium carbonate.:
"Relative to calcium, strontium was nearly unchanged in the limewater compared to the solid quicklime. The slight elevation in the limewater is above the background noise, however, since the emission signal from strontium is so strong. The reason for this slight elevation is that strontium is even less likely than calcium to precipitate onto the bottom of the limewater reservoir, and so stays more in solution than calcium."
This reference (below) says the solubility is 0.061 molar for strontium hydroxide, and since calcium hydroxide solubility is 0.0204 molar, it would seen strontium hydroxide is a bit more soluble.
Determination of activity product of strontium hydroxide by polarographic method. Kovalenko, P. N. Fiz.-Khim. Metody Analiza i Kontrolya Proizvodstva. (Rostov-on-Don: Rostovsk. Univ.) Sb. (1961), 80-5. From: Ref. Zh., Khim. 1962, Abstr. No. 9B555.
Abstract
The value of the activity product (La) of Sr(OH)2 was detd. on a polarograph M-7-2000 at 20°. The supporting electrolyte was 0.1N LiCl soln. The Sr(OH)2 soly. was min. at pH 12.9. The value of La was 9 ´ 10-4, and Sr(OH)2 soly. was 6.08 ´ 10-2 mole/l.
In reality, it is not simple to compare the solubility of strontium hydroxide to calcium hydroxide, since it depends a bit on pH:
Comparative study of the precipitation of calcium and strontium. Zhukova, L. A.; Chikov, V. S. USSR. Doklady TSKhA (1972), No. 188 235-9.
Abstract
The pH effect on the Ca or Sr content in ppts. from nitrate solns. contg. NaOH, Na2SiO3, or Na2CO3 at const. ionic strength 0.5 (NaNO3) was studied; pH was adjusted by adding variable amounts of NaOH or HNO3. Addn. of NaOH alone caused pptn. of Ca2+ to begin at pH 11.3, and pptn. of Sr2+, at pH 10.8, but at pH 10.8-12.8, the concn. of ca2+ in soln. was higher than that of Sr2+, i.e. the soly. of Ca(OH)2 was greater than that of Sr(OH)2. Above pH 12.8, the soly. of Ca(OH)2 was lower than that of Sr(OH)2. Addn. of Na2SiO3 caused pptn. of Ca2+ and Sr2+ to begin at pH 5.5 and 6, resp. In all cases, stoichiometric CaSiO3 pptd., and no Ca(OH)2 was obsd. at pH ³11.6. Addn. of Na2CO3 caused pptn. of Ca2+ and Sr2+ to begin at pH 5.5 and 8.4, resp.; the soly. of CaCO3 exceeded that of SrCO3 at all pH.