Tuesday's rally was a reminder of what can happen with a breakthrough in trade talks, Jim Cramer announced to his Mad Money viewers. When the trade war ends, he said, investors should expect an epic rally.

Cramer said today's loosening of sanctions against China's Huawei Technologies Co. Ltd. allowed the stock market to rally and give investors just a glimpse of what is possible if the trade war comes to an end. There are many stocks trading at very low valuations, that would be poised for huge moves to the upside if an agreement on trade were to be reached.

Today Qorvo (QRVO - Get Report) cut its earnings forecast by just 15 cents, but shares have fallen 24%. Meanwhile, Micron Technologies (MU - Get Report) trades at just five times earnings. Xilinx (XLNX - Get Report) has also fallen to ridiculous levels, according to Cramer.

Apple (AAPL - Get Report) was able to rally 1.9% today, but still has a Chinese cloud handing over its head. Nvidia (NVDA - Get Report) shares have been holding on near $155 a share, Cramer noted, but would also see an explosive pop without a trade war.

Finally, there are retailers like Dollar General (DG - Get Report) , which also source goods from China. Cramer said these too would be great investments post-trade wars, as would Caterpillar (CAT - Get Report) , which sells machinery into China.

Cramer and the AAP team are look at Home Depot (HD - Get Report) , which beat earnings expectations despite bad weather. Find out what they're telling their investment club members and get in on the conversation with a free trial subscription to Action Alerts Plus.

Off the Charts: Cannabis Stocks

In the "Off The Charts" segment, Cramer checked in with colleague Tim Collins over the charts of the cannabis stocks. 

Given the volatility of this group, Collins only used weekly charts to look at the cannabis stocks. He said there was nothing compelling in Aphria's (APHA) chart and Tilray (TLRY - Get Report) also was questionable. He was more bullish on the industry leader, Canopy Group (CGC - Get Report) .

Collins was most bullish on GW Pharmaceuticals (GWPH) , which is not a cannabis stock at all, but rather a drugmaker that draws its inspiration from compounds contained in cannabis. He noted an ascending triangle pattern and stochastics there were signaling a severely oversold condition.

Finally, Collins looked at Village Farms (VFF - Get Report) , a tiny speculative company with a cupping pattern that could signal a rally up to $20 a share. Cramer said he wasn't convinced by the technicals alone. Neither Collins nor Cramer were fans of Cronos (CRON - Get Report) . 

Executive Decision: Novartis 

For his "Executive Decision" segment, Cramer spoke with Vasant Narasimhan, CEO of Novartis (NVS - Get Report) , the drugmaker with shares up 7% for the year as some democratic presidential candidates call for a single payer model and "Medicare for all".

Narasimhan said the U.S. remains an ecosystem of incredible innovation and he's not advocating wholesale changes to the system, but rather smart reform to balance the distortions. He said many medicines are given on a chronic basis, but with new therapies, some diseases can be cured in a single dose, which means new payment plans and outcome-based treatments need to be considered. Novartis is leading the charge in Washington to help Congress and regulators begin thinking about these new treatments and new models.

Turning to the business of Novartis, Narasimhan noted that his company has 26 potential blockbuster treatments in its pipeline and there will be a string of exciting new launches beginning this year in the areas of cancer, eye disease and more. Yet with all of these new drugs coming to market, Novartis is still committed to spending $9 billion on research and development. 

On Real Money, Cramer keys in on the companies and CEOs he knows best. Get more of his insights with a free trial subscription to Real Money.

Executive Decision: Trex 

In his second "Executive Decision" segment, Cramer also sat down with Jim Cline, president and CEO of Trex (TREX - Get Report) , a stock that's down 20% from its highs after the company reported a five-cents-a-share earnings miss in April.

Cline admitted that Trex had a tough start to a new product launch that affected their earnings. He expected it will take one more quarter to work through those issues, paving the way for a strong second half. Cline noted that a cold, wet spring also delayed some home projects, but that also will recover during the back half of the year. Overall, Cline said Trex did not see any significant slowing of demand, their issues were all on the supply side.

Cline continued by explaining that Trex products are made from 95% recycled materials, including plastics and sawdust, making them better and cheaper than their all-natural counterparts. He said the environmental story of Trex is largely unknown to many people.

Finally, Cline said business remains strong in the commercial products division, where the company provides railings and other products to stadiums and other large venues. 

Cramer's 'Don't Buy' List -- At Least, Not Yet

In his "No-Huddle Offense" segment, Cramer said there are fewer and fewer stocks out there that will let you sleep at night. He offered a list of just a few of the sectors that are now off-limits until there's a reprieve in the trade war.

Financials topped Cramer's "don't buy" list as the inverted yield curve has proved to be challenging. While these stocks are cheap, he said they look like they will stay cheap for a very long time.

Investors also need to steer clear of the industrials, which are levered to growth in China, and many of the retailers, as we saw with hideous results from Kohl's Stores (KSS - Get Report) .

Healthcare, communications, energy and even the transports also made Cramer's list, leaving only Verizon (VZ - Get Report) , Procter & Gamble (PG - Get Report) , Amazon (AMZN - Get Report) and a handful of other names that are truly immune from these day-to-day market gyrations. 

Lightning Round

In the Lightning Round, Cramer was bullish on Kinder Morgan (KMI - Get Report) and McDonald's (MCD ) .

Cramer was bearish on Nektar Therapeutics (NKTR - Get Report) , Intel (INTC - Get Report) , L Brands (LB - Get Report) and Scientific Games (SGMS - Get Report) .

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At the time of publication, Cramer's Action Alerts PLUS had a position in HD, AAPL, NVDA, KSS, AMZN.