Lowe's (LOW) is the world's second largest retailer of home improvement products after Home Depot (HD). Walmart (WMT) and Target (TGT) also cater the home improvements market. Lowe's offers a wide range of home improvement products and installation services to individual home owners as well as professional builders. In addition to the physical stores, consumers can buy products through the company's dedicated website. Lowe's business is vulnerable to the housing market swings and the recent slowdown has affected its sales to a great extent in the past few years.

Spring has officially begun, and now may be the time to consider some investments that could add a little "spring" to your portfolio.

Topping the list are companies like Lowe's (LOW) and Home Depot (HD). They stand to benefit from the nicer weather as people head outdoors to work on the garden, plant new beds, maintain the lawn, and take care of home improvements.

What did you think of Home Depot's (HD) earnings report? I rather enjoyed it. And I think the future may be bright for the retailer and arch enemy of Lowe's (LOW).

According to TheStreet.com, net income calculated out to 36 cents per share for the fourth quarter. This was five pennies better than the overall estimate. Same-store sales experienced an increase of 3.9%. And management's forecast for the full fiscal year was upgraded.

The past week's data-point-of-consequence for investors had to be investment decisions by Warren Buffett's Berkshire Hathaway (BRK.A).

Buffett ended positions in several stocks in the fourth quarter, including the Bank of America (BAC), Nike (NKE), Fiserv (FISV), Becton Dickinson (BDX), Comcast Corp. (CMCSA), Lowe's Co.s (LOW), Nalco (NLC) and Nestle (NSRGY), according to a filing, The Wall Street Journal reported.

Berkshire added to a holding of only one stock in the fourth quarter: Wells Fargo (WFC).

Analyst Upgrades

• Home Depot (HD) to buy from neutral at Goldman.
• Delta Air Lines (DAL) to buy from neutral at BofA/Merrill.
• Heico (HEI) to outperform from sector perform at RBC Capital.
• Royal Dutch Shell (RDS.A) to outperform from neutral at Credit Suisse.
• MB Financial (MBFI) to outperform from neutral at RW Baird.
• Quest Diagnostics (DGX) to equal weight from underweight at Morgan Stanley.
• Oshkosh (OSK) to neutral from underweight at JPMorgan.
• Volterra (VLTR) and Silicon Laboratories (SLAB) to buy from neutral at Roth Capital.
• Ascena Retail Group (ASNA) to overweight from neutral at Piper Jaffray.
• Cytec Industries (CYT) to buy from hold at Deutsche Bank.

Analyst Upgrades

• Walgreen (WAG) and Triumph Group (TGI) to buy from neutral at UBS.
• Focus Media (FMCN) to buy from neutral at Goldman.
• Home Depot (HD) to outperform from market perform at FBR Capital.
• Arbitron (ARB) to overweight from neutral at JPMorgan.
• Waddell & Reed (WDR) and Legg Mason (LM) to overweight from equal weight, and Janus Capital (JNS) to overweight from underweight, at Barclays.
• Central Euro Media (CETV) to buy from hold at Deutsche Bank.
• GenOn Energy (GEN) and Ntelos (NTLS) to outperform from sector perform at RBC Capital.
• Cooper Tire (CTB) to buy from neutral and Goodyear Tire (GT) to buy from underperform at BofA/Merrill.

Lowe's (LOW) reported Monday morning that its third-quarter profit was $404 million or 29 cents a share, an increase from $344 million or 23 cents a share a year earlier. Results included charges of two cents and one cent respectively. Revenue climbed 1.9% to $11.59 billion. Same-store sales were rose slightly.

The company had forecast earnings of 28 cents to 32 cents and revenue up 3% to 5%. A year earlier, revenue had declined 3%. Gross margins rose to 35% from 34.2%.

"Home Prices Are About to Bottom" was the headline for the Barron's cover story the week of July 14, 2008. The story explained that the housing market should level off in many areas of the country by the end of the year.

I have made some equally unfortunate prognostications in my tenure at BloggingStocks, so my purpose is not to poke fun at Barron's but to point out that here we are, over two years later, and it is still debatable whether the housing market has bottomed out.

Last week, Macy's (M) and JCPenney (JCP) kicked off the retail earnings season by posting better-than-expected earnings for the most recent quarter. Many more quarterly reports from retailers are due this week, and by and large expectations of analysts surveyed by Thomson Reuters are high.

Walmart (WMT), the king of retailers, is expected to buck the trend, though. Analysts anticipate that the Bentonville-based company will report that its third-quarter earnings grew only 6.7% year-over-year to 90 cents per share. During the three months that ended in October, Walmart announced an acquisition in South Africa and kicked-off the holiday shopping season, and revenue for that period is predicted to have risen 3.0% to $102.4 billion. Looking ahead to the fourth quarter, analysts so far expect sequential and year-over-year growth of both earnings and revenue. Walmart results have not fallen short of consensus estimates in the past five quarters.

Analyst Upgrades

• Standpoint Research upgraded Bank of America (BAC) to accumulate from hold based on valuation.
• UBS upgraded First Solar (FSLR) to buy from neutral and raised its price target to $150 from $136. The firm believes global solar demand will be higher than expected in 2010 and 2011.
• Goldman upgraded Lowe's (LOW) to buy from neutral and has a $24 target on the stock. The firm upgraded shares given the company's margin recovery which will drive EPS growth in 2H10.
• Zep Inc. (ZEP) was upgraded to buy from neutral at Janney Montgomery.
• Rosetta Resources (ROSE) was upgraded to buy from neutral at SunTrust.
• Matrixx Initiatives (MTXX) was upgraded to buy from hold at Roth Capital.

Home Depot (HD), the main rival of Lowe's (LOW), closed higher yesterday by 3.4%, finishing out the session at a price of $28.31. It has a ways to go before reaching the 52-week high of $37.03. Will investors push the stock to that level after the second-quarter report?

I'm not sure that will happen anytime soon, but the data wasn't so bad. Earnings per share grew 9% to 72 cents -- a penny ahead of expectations. Same-store sales expanded by 1.7%.