1 Month Hiking in New Zealand
 

I am planning a one month trip to New Zealand between the month of mid-February to May (flexible). I will be going with my husband and the main purpose of the trip will be to get in as much hiking as possible. We are not opposed to tenting; however, understand that NZ has many huts around and that or hotels/motels/B&Bs would be the preference. I am trying to decide whether it is feasible to rent a house/room for the month and do day-hikes/multi-day hikes from a central location or if it is best to go hut to hut? Any suggestions would be great... at this point we are just brainstorming ideas. I have read about the 9 great walks - any feedback on whether to pick some of these or alternatives would be great. Also, is it recommended to book through a hiking group instead of going it alone? We have hiked alone (party of 2) through Italy and other countries just want to make sure that NZ hikes are marked well and easy to follow.

Best have a good look at a map of New Zealand and decide which walks you really want to do.
One location won't work for a base. They are scattered all over the country and some are very isolated. You would need to rent a car to get to the start of the walks and some are one way so there is the problem of getting your car to the end point.
Tongariro Northern Circuit is off the main highway through the North Island so that would be doable. It's an awesome area of the country with it's desert landscape and mountains rising up.
Abel Tasman is close to Nelson and a beautiful place with golden beaches. Some day walks here would be lovely.
Routeburn, Kepler and Milford are big 3 of the South Island and organised tour groups will take you through the walk in style. The huts at Milford book out within minutes of the bookings being open.
The Heaphy is also in the Nelson area but it's walked one way or the other so you have to pay for a flight back, or a runner to drive your car to Karamea. It's probably a bit isolated as you have to get to Golden Bay for the start of the walk.
Forget Rakiura or Lake Waikaremoana - they are too isolated and you would waste valuable holiday time just getting there.
In 4 weeks you could explore 3 areas:
Drive Auckland - Taupo - Tongariro NC.
TNC - Wellington - ferry trip to Picton - Nelson for Abel Tasman.
Fly Nelson to Queenstown for one of the big 3 walks.
Queenstown would work as a base as there are quite a lot of nice day walks from there. You'd probably need a car to get to them.

Your question is so broad, but you did say you were brainstorming. In terms of hiking, or tramping as it's called here, New Zealand has everything you're looking for, from hour-long walks, several-hour walks, overnight and multi-day tramps with hut accommodation, and even something you aren't looking for—a long-distance tramping route that takes several months to complete (Te Araroa).

If you haven't yet done so, start by exploring the Dept. of Conservation's website under the categories of "Great Walks" and "Walking and Tramping":
http://www.doc.govt.nz
And narrowed-down options on "Must see walks and tramps":
http://www.doc.govt.nz/mustseewalks
Hut bookings are also made through the above Dept. of Conservation website. Their website is an incredible resource, that also offers information about NZ's unique fauna and flora.

You can find tramps on a map under "Find places to go walking and tramping."
NZ tourism also has a brochure with a map showing popular walks: http://www.newzealand.com/travel/library/j10940_6.pdf
Another useful link:
http://nzwalksinfo.co.nz

The Dept. of Conservation breaks down their tracks (trails) into categories (from "Easiest" to "Expert").
http://www.doc.govt.nz/parks-and-rec...ck-categories/
The "Advanced" and "Expert" tracks are described as "unformed," if you plan to walk these, follow DOC's recommendations and definitely hire a personal locator beacon. Every region you visit should have an I-Site Tourism information office and often a DOC office. If you have questions about track conditions, these folks will know. They'll also have maps and such.

You'd probably like to experience a variety of different environments, and you can in New Zealand: from alpine to coastal, lush rainforest to stark volcanic terrain, and more. If so, it wouldn't work to base yourself in one place for the month. You might want to tramp on both North and South Islands, or on just one island, or want to add a third, smaller island (Stewart Island off the bottom of the SI). Chances are you'll want to move around. NZ roads can be narrow and curvy. Some climb through steep mountain passes, others snake along sharp drop-offs. You'll probably drive on some gravel roads, have to slow down for one-lane bridges, maybe get stuck behind a slow-moving campervan or three of them. So it will take time and patience to drive from place to place. Once you've figured out your route, you can check drive distances at: https://www.aa.co.nz/travel/time-and...ce-calculator/

February and March are high season, so Great Walks must be booked ahead, some of these, such as the famed Milford Track, well in advance. See: https://blog.doc.govt.nz/2015/03/19/...hings-to-know/
http://www.doc.govt.nz/parks-and-rec...-and-bookings/
Huts on popular tracks should be booked as well, for example Mueller Hut at Mt. Cook:
http://www.doc.govt.nz/parks-and-rec...s/mueller-hut/
April is a popular month as well, with school holidays from Saturday 14 April to Sunday 29 April, 2018. It'll starts to get colder on the South Island, and days grow shorter.

In May, because of the weather some track and hut conditions can change.
For example, on this link for the Routeburn Track, read the advisories under "Outside the Great Walks Season (4 May 2017 - 23 October 2017):
http://www.doc.govt.nz/parks-and-rec...-walks-season/

People on this forum can recommend many beautiful, must-see, well-marked, easy to follow tracks for you (especially Melnq8). I've only been on day hikes and they've always been well-marked. There are so many people on some of them, it would be impossible to get lost. This being said, trampers do wander off track, or injure themselves, or get trapped by conditions that quickly changed. In summer, it seems I read about a tramper being rescued every other day. Here are a few recent rescues:
http://www.stuff.co.nz/southland-tim...-National-Park
http://www.nzherald.co.nz/nz/news/ar...ectid=11797263
http://www.stuff.co.nz/national/8847...-national-park
http://www.nzherald.co.nz/nz/news/ar...ectid=11797120

Not sure what you mean by a hiking group. Do you mean guided hikes? RalphR reported on his guided walks with Ultimate Hikes:
http://www.fodors.com/community/aust...s-nov-2010.cfm
https://www.ultimatehikes.co.nz/en
Or something like this?
http://www.walkinglegends.com/new-ze...ided-day-walk/

The city I live in has a few tramping clubs. I'm sure most NZ cities and towns have tramping clubs. This one says it welcomes non-members on their trips.
http://otmc.co.nz/index.html

As mentioned above, start with DOC. An excellent resource for tramping in NZ.

Also mentioned above, one base just does not work in NZ.

NZ has wonderful tracks at virtually every turn. The great walks are just a drop in the bucket. There are so many other tracks that first time visitors haven't even heard of.

I've never seen the advantage of paying a company big bucks to lead me down a well marked track, but the tour operators do have access to nicer accommodation on some of the multi-days hikes. You absolutely do not need a guide or operator unless that's just your preference.

Tracks in NZ are well marked, categorized by difficulty and very well maintained. The NZ government does a fabulous job of maintaining its tracks, and puts other countries to shame.

My husband and I have been hiking in NZ since the early 90's. I have several very detailed trip reports posted here on Fodor's describing those walks - most on the SI, which we much prefer over the North Island.

Our MO is to spend a minimum of three nights in a given area, which gives us two full days to explore the tracks of a particular area. Then we move on to the next.

If you are interested in reading some of these reports, just click on my name and scroll down through my trip reports (there are several pages of TRs).

As your trip evolves, we Fodorites can help you with more specific information, but for now you need to narrow down exactly what interests you most, and then go from there.

Melnq8, if I could afford it, I'd gladly take Ultimate Hikes Milford Track trip. I love the idea of not having to carry more than a day pack (and a heavy camera) and then having access to "hot showers, delicious 3 course meals, beer & wine, heating, drying rooms and warm snug beds."

I hear you Diamantina. Not to mention I might need to be flown out:)