Choosing a fresh Christmas tree that stays healthy all season is easy once you know the clues, three-time Emmy winner James Pearse Connelly told Homes.com.

Follow these tips.

Shoppers should start with a plan, said Connelly, a set designer whose portfolio includes "The Kelly Clarkson Show," "Top Chef," "Wheel of Fortune" and "The Voice."

"Ask yourself when and what, "Connelly said in an email. "When do you think you’ll take the tree down and what will you use to decorate? If it’s early December and you’re going away after the holidays, consider a stronger tree that can receive your treescape and hold your keepsakes."

Size is a key feature people look for when picking a tree, Connelly said.

Measure the space of the display room before heading to the tree farm, according to the Chesterfield, Missouri-based National Christmas Tree Association, whose 700 member farms and 4,000 affiliated businesses produce about 75% of farm-raised Christmas trees in the nation. Start with the ceiling — trees appear smaller against the sky when in a field. Also measure the width of the area of the room.

Most trees on farms are trimmed to an 80% taper — so a 10-foot-tall tree will be 8 feet at the bottom. Trees that fit the room vertically may be too big horizontally.

Don’t forget to measure the stand and make sure it is compatible with the trunk size considered.

The annual selection of the Christmas tree is a tradition for many families. Here are the features of some of the most popular trees, according to the Real Christmas Tree Board, a national research organization based in Howell, Michigan funded by North American Christmas tree farmers.

• Fraser fir: Excellent needle retention and stiff branches make it ideal for supporting ornaments
• Douglas fir: Softer branches and needles are good for light-weight ornaments
• White pine: Long, soft green needles pair well with light-weight ornaments while excellent needle retention is ideal for wreaths and greenery
• Scotch pine: Stiff branches, dense needles with good needle retention support heavier ornaments
• Blue spruce: Stiff branches, but very prickly needles with needle retention fade after two to three weeks
• Balsam fir: Short, dark green needles and excellent triangular shape are a natural choice for displaying ornaments

Trees with longer, looser needles are great for tinsel and lights, said Connelly. Trees with shorter, sharper needles like fir and spruce can support heavier ornaments and even candles. The blue spruce has "the strongest branches and holds its needles the longest over the season," he said.

“I want something that has that classic symmetrical shape, so it looks good on all angles and has a visual versatility to it in case we change our mind to another theme," he said. "Definitely strong branches because I’ll want to populate it with as much as I can for color pops and theming. It also needs to look as real as possible."

He added that there's nothing wrong with artificial trees. "In fact, 90% of the trees I use are artificial and typically last me way over 5 to 10 seasons. For that, I typically lean in classic. A Fraser fir is a can’t lose bet. But sometimes I want it to look a little more textured so I’ll go with white fir or Aspen fir. Or even a blue spruce.”

Connelly once designed a Christmas set for the late-night show "Lopez Tonight" for George Lopez. The entertainer wanted a black tree, which was uncommon, he said. Decorating was a challenge, but in the end, Connelly chose to use a ton of different purple and white lights. The challenge taught him how to decorate outside of traditionalism while adding fun and intrigue to the tree, he said.  

Form is important because it affects how a tree is lit and decorated, said Connelly. Traditional trees are pyramidal with consistent, evenly spaced branches. This highlights the exterior of the tree. More sparsely branched trees allow for opportunities to light and decorate the interior.

The types of ornaments displayed could help determine the form. Old-fashioned or heirloom ornaments look best on a tree with a unique character like a Douglas fir.

Flexible needles are a sign of a healthy tree, said Rick Dungey, the National Christmas Tree Association's executive director. "Take a keep-it-simple approach," he said. "Rub a branch with your hand, close your hand around it. The needles should not come off easily."

"The most fun thing to consider is smell," said Connelly. "Let’s be honest, the smell of a real Christmas tree in a home is unbeatable. It can smell sweet, fresh and piney and have different levels of fragrance."

A few important clues about a tree's health are excessive needle loss, discolored foliage, a musty odor, pliability and wrinkled bark. "If you look at it and it has a lot of brown foliage, pass it by," Dungey said.

Daily maintenance will keep a tree looking great throughout the holidays.

Cut about a half inch of wood from the base of the tree before putting it in a stand. Make the cut perpendicular to the stem axis — cutting an angle or a V-shape will reduce the amount of water to the tree and make it difficult to place it in a stand.

Place the tree in water within four to six hours after it's been cut.

The tree will absorb a lot of water in the first few days. This is because evergreens become dormant in the fall and push water from the trunk into the roots to keep them from freezing. The tree must take in the lost amount.

Displaying trees in water in a traditional reservoir type stand is the most effective way of maintaining their freshness and minimizing needle loss.

Check the stand daily so water does not go below the base of the tree. Many stands are configured so they show water even though the base of the tree is no longer submerged.

Keep trees away from heat — fireplaces, heaters, heat vents and direct sunlight. A lower temperature will slow the drying process.

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